A case of linear IgA bullous dermatosis with IgA anti-type VII collagen autoantibodies.

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Hashimoto, T; Ishiko, A; Shimizu, H; Tanaka, T; Dodd, H J; Bhogal, B S; Black, M M; Nishikawa, T

1996-02-01

In this study we present a patient with the sublamina densa type of linear IgA bullous dermatosis (LABD), with IgA autoantibodies reactive with the 290-kDa type VII collagen (the epidermolysis bullosa acquisita (EBA) antigen) and with immunoblotting of normal human dermal extracts. The clinical and histological features of the present case were compatible with those of LABD but quite different from those of EBA. Although EBA sera reacted with the bacterial fusion protein of the N-terminal globular (NC1) domain of type VII collagen, this patient's serum did not show reactivity. Furthermore, ultrastructural localization of target epitopes on the anchoring fibrils in this patient was considerably different from EBA. These results indicate that, whereas EBA antibodies react with the NC1 domain of type VII collagen, the epitope in this case is different from that of EBA (and is most likely on the central triple helical domain). This difference may be responsible for the clinical presentation in this patient being distinct from that of EBA.

Protumorigenic role of HAPLN1 and its IgV domain in malignant pleural mesothelioma.

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Ivanova, Alla V; Goparaju, Chandra M V; Ivanov, Sergey V; Nonaka, Daisuke; Cruz, Christina; Beck, Amanda; Lonardo, Fulvio; Wali, Anil; Pass, Harvey I

2009-04-15

Tumor extracellular matrix (ECM) plays a crucial role in cancer progression mediating and transforming host-tumor interactions. Targeting the ECM is becoming an increasingly promising therapeutic approach in cancer treatment. We find that one of the ECM proteins, HAPLN1, is overexpressed in the majority of mesotheliomas. This study was designed to characterize the protumorigenic role of HAPLN1 in mesothelioma. Overexpression of HAPLN1 was assessed and validated on a large set of normal/mesothelioma specimens on the RNA and protein levels. We also analyzed DNA copy number alterations in the HAPLN1 genomic locus using the array-based comparative genomic hybridization representational oligonucleotide microarray analysis tool. Tumorigenic activities of the HAPLN1 domains were evaluated in vitro on mesothelioma cells transfected with HAPLN1-expressing constructs. We found that HAPLN1 is 23-fold overexpressed in stage I mesothelioma and confirmed it for 76% samples (n = 53) on RNA and 97% (n = 40) on protein levels. The majority of lung cancers showed no differential expression of HAPLN1. Analysis of DNA copy number alterations identified recurrent gain in the 5q14.3 HAPLN1 locus in approximately 27% of tumors. Noteworthy, high expression of HAPLN1 negatively correlated with time to progression (P = 0.05, log-rank test) and overall survival (P = 0.006). Proliferation, motility, invasion, and soft-agar colony formation assays on mesothelioma cells overexpressing full-length HAPLN1 or its functional domains strongly supported the protumorigenic role of HAPLN1 and its SP-IgV domain. Overexpression of HAPLN1 and its SP-IgV domain increases tumorigenic properties of mesothelioma. Thus, targeting the SP-IgV domain may be one of the therapeutic approaches in cancer treatment.

Antimicrobial activity of a novel hypervariable immunoglobulin domain-containing receptor Dscam in Cherax quadricarinatus.

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Li, Dan; Yu, Ai-Qing; Li, Xue-Jie; Zhu, You-Ting; Jin, Xing-Kun; Li, Wei-Wei; Wang, Qun

2015-12-01

Down syndrome cell adhesion molecule (Dscam) mediates innate immunity against pathogens in arthropods. Here, a novel Dscam from red claw crayfish Cherax quadricarinatus (CqDscam) was isolated. The CqDscam protein contains one signal peptide, ten immunoglobulin domains, six fibronectin type III domains, one transmembrane domain and cytoplasmic tail. CqDscam phylogenetically clustered with other invertebrate Dscams. Variable regions of CqDscam in N-terminal halves of Ig2 and Ig3 domains, complete Ig7 domain and TM domain can be reshuffled after transcription to produce a deluge of >37,620 potential alternative splice forms. CqDscam was detected in all tissues tested and abundantly expressed in immune system and nerve system. Upon lipopolysaccharides (LPS) and b-1, 3-glucans (Glu) challenged, the expression of CqDscam was up-regulated, while no response in expression occurred after injection with peptidoglycans (PG). Membrane-bound and secreted types of CqDscam were separated on the protein level, and were both extensively induced post LPS challenge. Membrane-bound CqDscam protein was not detected in the serum, but localized to the hemocyte surface by immuno-localization assay. In the antimicrobial assays, the recombinant LPS-induced isoform of CqDscam protein displayed bacterial binding and growth inhibitory activities, especially with Escherichia coli. These results suggested that CqDscam, as one of pattern-recognition receptors (PRRs), involved in innate immune recognition and defense mechanisms in C. quadricarinatus, possibly through alternative splicing. Copyright © 2015 Elsevier Ltd. All rights reserved.

SNP8NRG433E1006 NEUREGULIN-1 GENETIC VARIATION IN BATAKS ETHNIC WITH SCHIZOPHRENIA PARANOID AND HEALTHY CONTROL

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Elmeida Effendy

2014-05-01

Full Text Available The neuregulin 1 (NRG1 gene which influences the development of white matter connectivity has been associated with schizophrenia. It influences neuronal migration, synaptogenesis, gliogenesis, neuron-glia communication, myelination, and neurotransmission in the brain and others. NRG1 is located in 8p13, and it is frequently replicated in schizphrenia. SNP8NRG433E1006 gene NRG1 is one of core at risk haplotype of schizphrenia. This study looked forward differences SNP8NRG433E1006 neuregulin 1 between Bataks ethnic with schizophrenia paranoid and Bataks ethnic healthy control. Methods: Batak ethnic with schizophrenia paranoid were recruited and interviewed with semi-structured MINI ICD-X to establish the diagnosis. All the eligible subjects were requested their permission for blood sampling. Healthy Batak ethnic were also recruited by mathcing the age and gender. The blood samples went through DNA isolation, Nested PCR, and DNA sequencing. Results: Ninety three subjects were recruited, but only 74 blood samples were succesfully sequenced. We found three types of polymorphisms, i.e. G/A allele at base pair (bp 76, G/T allele at bp 112, and deletion at bp 110 in Batak ethnic with schizophrenia. There were two kind sequences at bp 113-116 in Batak ethnics, and Batak ethnics with ATCG were at higher risk for having schizophrenia. This study support that NRG1 is a schizophrenia-susceptibility gene.

The human TREM gene cluster at 6p21.1 encodes both activating and inhibitory single IgV domain receptors and includes NKp44.

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Allcock, Richard J N; Barrow, Alexander D; Forbes, Simon; Beck, Stephan; Trowsdale, John

2003-02-01

We have characterized a cluster of single immunoglobulin variable (IgV) domain receptors centromeric of the major histocompatibility complex (MHC) on human chromosome 6. In addition to triggering receptor expressed on myeloid cells (TREM)-1 and TREM2, the cluster contains NKp44, a triggering receptor whose expression is limited to NK cells. We identified three new related genes and two gene fragments within a cluster of approximately 200 kb. Two of the three new genes lack charged residues in their transmembrane domain tails. Further, one of the genes contains two potential immunotyrosine Inhibitory motifs in its cytoplasmic tail, suggesting that it delivers inhibitory signals. The human and mouse TREM clusters appear to have diverged such that there are unique sequences in each species. Finally, each gene in the TREM cluster was expressed in a different range of cell types.

Determinants in the Ig Variable Domain of Human HAVCR1 (TIM-1) Are Required To Enhance Hepatitis C Virus Entry.

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Kachko, Alla; Costafreda, Maria Isabel; Zubkova, Iryna; Jacques, Jerome; Takeda, Kazuyo; Wells, Frances; Kaplan, Gerardo; Major, Marian E

2018-03-15

Hepatitis C virus (HCV) is the leading cause of chronic hepatitis in humans. Several host molecules participate in HCV cell entry, but this process remains unclear. The complete unraveling of the HCV entry process is important to further understand viral pathogenesis and develop therapeutics. Human hepatitis A virus (HAV) cellular receptor 1 (HAVCR1), CD365, also known as TIM-1, functions as a phospholipid receptor involved in cell entry of several enveloped viruses. Here, we studied the role of HAVCR1 in HCV infection. HAVCR1 antibody inhibited entry in a dose-dependent manner. HAVCR1 soluble constructs neutralized HCV, which did not require the HAVCR1 mucinlike region and was abrogated by a mutation of N to A at position 94 (N94A) in the Ig variable (IgV) domain phospholipid-binding pocket, indicating a direct interaction of the HAVCR1 IgV domain with HCV virions. However, knockout of HAVCR1 in Huh7 cells reduced but did not prevent HCV growth. Interestingly, the mouse HAVCR1 ortholog, also a phospholipid receptor, did not enhance infection and a soluble form failed to neutralize HCV, although replacement of the mouse IgV domain with the human HAVCR1 IgV domain restored the enhancement of HCV infection. Mutations in the cytoplasmic tail revealed that direct HAVCR1 signaling is not required to enhance HCV infection. Our data show that the phospholipid-binding function and other determinant(s) in the IgV domain of human HAVCR1 enhance HCV infection. Although the exact mechanism is not known, it is possible that HAVCR1 facilitates entry by stabilizing or enhancing attachment, leading to direct interactions with specific receptors, such as CD81. IMPORTANCE Hepatitis C virus (HCV) enters cells through a multifaceted process. We identified the human hepatitis A virus cellular receptor 1 (HAVCR1), CD365, also known as TIM-1, as a facilitator of HCV entry. Antibody blocking and silencing or knockout of HAVCR1 in hepatoma cells reduced HCV entry. Our findings that the

Rapid isolation of IgNAR variable single-domain antibody fragments from a shark synthetic library.

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Shao, Cui-Ying; Secombes, Chris J; Porter, Andrew J

2007-01-01

The immunoglobulin isotype IgNAR (Novel Antigen Receptor) was discovered in the serum of the nurse shark (Ginglymostoma cirratum) and wobbegong shark (Orectolobus maculates) as a homodimer of two protein chains, each composed of a single variable domain (V) domain and five constant domains. The IgNAR variable domain contains an intact antigen-binding site and functions as an independent domain able to react to antigen with both high specificity and affinity. Here we describe the successful construction of a synthetic phage-displayed library based upon a single anti-lysozyme clone HEL-5A7 scaffold, which was previously selected from an immune IgNAR variable domain library. The complementarity-determining region 3 (CDR3) loop of this clone was varied in both length and composition and the derived library was used to pan against two model proteins, lysozyme and leptin. A single anti-lysozyme clone (Ly-X20) and anti-leptin clone (Lep-12E1) were selected for further study. Both clones were shown to be functionally expressed in Escherichia coli, extremely thermostable and bind to corresponding antigens specifically. The results here demonstrate that a synthetic IgNAR variable domain library based on a single framework scaffold can be used as a route to generate antigen binders quickly, easily and without the need of immunization.

RhNRG-1β Protects the Myocardium against Irradiation-Induced Damage via the ErbB2-ERK-SIRT1 Signaling Pathway.

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Anxin Gu

Full Text Available Radiation-induced heart disease (RIHD, which is a serious side effect of the radiotherapy applied for various tumors due to the inevitable irradiation of the heart, cannot be treated effectively using current clinical therapies. Here, we demonstrated that rhNRG-1β, an epidermal growth factor (EGF-like protein, protects myocardium tissue against irradiation-induced damage and preserves cardiac function. rhNRG-1β effectively ameliorated irradiation-induced myocardial nuclear damage in both cultured adult rat-derived cardiomyocytes and rat myocardium tissue via NRG/ErbB2 signaling. By activating ErbB2, rhNRG-1β maintained mitochondrial integrity, ATP production, respiratory chain function and the Krebs cycle status in irradiated cardiomyocytes. Moreover, the protection of irradiated cardiomyocytes and myocardium tissue by rhNRG-1β was at least partly mediated by the activation of the ErbB2-ERK-SIRT1 signaling pathway. Long-term observations further showed that rhNRG-1β administered in the peri-irradiation period exerts continuous protective effects on cardiac pump function, the myocardial energy metabolism, cardiomyocyte volume and interstitial fibrosis in the rats receiving radiation via NRG/ErbB2 signaling. Our findings indicate that rhNRG-1β can protect the myocardium against irradiation-induced damage and preserve cardiac function via the ErbB2-ERK-SIRT1 signaling pathway.

The retinal specific CD147 Ig0 domain: from molecular structure to biological activity

OpenAIRE

Redzic, Jasmina S.; Armstrong, Geoffrey S.; Isern, Nancy. G.; Jones, David N.M.; Kieft, Jeffrey S.; Eisenmesser, Elan Zohar

2011-01-01

CD147 is a type I transmembrane protein that is involved in inflammatory diseases, cancer progression, and multiple human pathogens utilize CD147 for efficient infection. In several cancers, CD147 expression is so high that it is now used as a prognostic marker. The two primary isoforms of CD147 that are related to cancer progression have been identified, differing in their number of immunoglobulin (Ig)-like domains. These include CD147 Ig1-Ig2 that is ubiquitously expressed in most tissues a...

A novel form of the membrane protein CD147 that contains an extra Ig-like domain and interacts homophilically

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Brown Marion H

2003-11-01

Full Text Available Abstract Background CD147 is a broadly distributed integral membrane glycoprotein with two Ig-like domains implicated in a wide range of functions. It is associated at the cell surface with the monocarboxylate transporters MCT1 and 4 but interactions of the extracellular region have not been characterised. Results We report the characterisation of a form of CD147 with an additional membrane-distal Ig-like domain. In contrast to the two domain form, this three domain form of CD147 interacts homophilically. Surface plasmon resonance analysis using recombinant proteins showed that the interaction was of low affinity (KD ~ 40 μM and this is typical of many interactions between membrane proteins. cDNA for the 3 domain form are rare but have been identified in human and mouse retina. Conclusion The finding that the three domain form of CD147 has an extracellular ligand, that is it interacts homophilically, suggests this interaction may be important in aligning lactate transporters in the retina where lactate is an important metabolite.

Clinical significance of overexpression of NRG1 and its receptors, HER3 and HER4, in gastric cancer patients.

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Yun, Sumi; Koh, Jiwon; Nam, Soo Kyung; Park, Jung Ok; Lee, Sung Mi; Lee, Kyoungyul; Lee, Kyu Sang; Ahn, Sang-Hoon; Park, Do Joong; Kim, Hyung-Ho; Choe, Gheeyoung; Kim, Woo Ho; Lee, Hye Seung

2018-03-01

Neuregulin 1 (NRG1), a ligand for human epidermal growth factor (HER) 3 and HER4, can activates cell signaling pathways to promote carcinogenesis and metastasis. To investigate the clinicopathologic significance of NRG1 and its receptors, immunohistochemistry was performed for NRG1, HER3, and HER4 in 502 consecutive gastric cancers (GCs). Furthermore, HER2, microsatellite instability (MSI), and Epstein-Barr virus (EBV) status were investigated. NRG1 gene copy number (GCN) was determined by dual-color fluorescence in situ hybridization (FISH) in 388 available GCs. NRG1 overexpression was observed in 141 (28.1%) GCs and closely correlated with HER3 (P = 0.034) and HER4 (P overexpression was significantly associated with aggressive features, including infiltrative tumor growth, lymphovascular, and neural invasion, high pathologic stage, and poor prognosis (all P overexpression as an independent prognostic factor for survival (P = 0.040). HER3 and HER4 expressions were observed in 157 (31.3%) and 277 (55.2%), respectively. In contrast to NRG1, expression of these proteins was not associated with survival. NRG1 GCN gain (GCN ≥ 2.5) was detected in 14.7% patients, including two cases of amplification, and was moderately correlated with NRG1 overexpression (κ, 0.459; P overexpression in GC, overexpression of their ligand, NRG1, was associated with aggressive clinical features and represented an independent unfavorable prognostic factor. Therefore, NRG1 is a potential prognostic and therapeutic biomarker in GC patients.

DTNBP1, NRG1, DAOA, DAO and GRM3 polymorphisms and schizophrenia: an association study

DEFF Research Database (Denmark)

Jönsson, Erik G; Saetre, Peter; Vares, Maria

2009-01-01

BACKGROUND: Several studies of the dystrobrevin-binding protein 1 gene (DTNBP1), neuregulin 1 (NRG1), D-amino-acid oxidase (DAO), DAO activator (DAOA, G72), and metabotropic glutamate receptor 3 (GRM3) genes have suggested an association between variants of these genes and schizophrenia. METHODS....... However, after correction for multiple testing, there were no statistically significant allele, genotype or haplotype case-control differences. CONCLUSIONS: The present Scandinavian results do not verify previous associations between the analyzed DTNBP1, NRG1, DAO, DAOA, and GRM3 gene polymorphisms...

BACE1-Dependent Neuregulin-1 Signaling: An Implication for Schizophrenia

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Zhengrong Zhang

2017-09-01

Full Text Available Schizophrenia is a chronic psychiatric disorder with a lifetime prevalence of about 1% in the general population. Recent studies have shown that Neuregulin-1 (Nrg1 is a candidate gene for schizophrenia. At least 15 alternative splicing of NRG1 isoforms all contain an extracellular epidermal growth factor (EGF-like domain, which is sufficient for Nrg1 biological activity including the formation of myelin sheaths and the regulation of synaptic plasticity. It is known that Nrg1 can be cleaved by β-secretase (BACE1 and the resulting N-terminal fragment (Nrg1-ntf binds to receptor tyrosine kinase ErbB4, which activates Nrg1/ErbB4 signaling. While changes in Nrg1 expression levels in schizophrenia still remain controversial, understanding the BACE1-cleaved Nrg1-ntf and Nrg1/ErbB4 signaling in schizophrenia neuropathogenesis is essential and important. In this review paper, we included three major parts: (1 Nrg1 structure and cleavage pattern by BACE1; (2 BACE1-dependent Nrg1 cleavage associated with schizophrenia in human studies; and (3 Animal studies of Nrg1 and BACE1 mutations with behavioral observations. Our review will provide a better understanding of Nrg1 in schizophrenia and a potential strategy for using BACE1 cleavage of Nrg1 as a unique biomarker for diagnosis, as well as a new therapeutic target, of schizophrenia.

PD-1 immunoreceptor inhibits B cell receptor-mediated signaling by recruiting src homology 2-domain-containing tyrosine phosphatase 2 to phosphotyrosine

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Okazaki, Taku; Maeda, Akito; Nishimura, Hiroyuki; Kurosaki, Tomohiro; Honjo, Tasuku

2001-01-01

PD-1 is an immunoreceptor that belongs to the immunoglobulin (Ig) superfamily and contains two tyrosine residues in the cytoplasmic region. Studies on PD-1-deficient mice have shown that PD-1 plays critical roles in establishment and/or maintenance of peripheral tolerance, but the mode of action is totally unknown. To study the molecular mechanism for negative regulation of lymphocytes through the PD-1 receptor, we generated chimeric molecules composed of the IgG Fc receptor type IIB (FcγRIIB) extracellular region and the PD-1 cytoplasmic region and expressed them in a B lymphoma cell line, IIA1.6. Coligation of the cytoplasmic region of PD-1 with the B cell receptor (BCR) in IIA1.6 transformants inhibited BCR-mediated growth retardation, Ca2+ mobilization, and tyrosine phosphorylation of effector molecules, including Igβ, Syk, phospholipase C-γ2 (PLCγ2), and ERK1/2, whereas phosphorylation of Lyn and Dok was not affected. Mutagenesis studies indicated that these inhibitory effects do not require the N-terminal tyrosine in the immunoreceptor tyrosine-based inhibitory motif-like sequence, but do require the other tyrosine residue in the C-terminal tail. This tyrosine was phosphorylated and recruited src homology 2-domain-containing tyrosine phosphatase 2 (SHP-2) on coligation of PD-1 with BCR. These results show that PD-1 can inhibit BCR signaling by recruiting SHP-2 to its phosphotyrosine and dephosphorylating key signal transducers of BCR signaling. PMID:11698646

Detection of FMD virus type specific IgG1, IgG2 and IgA antibodies in milk and serum of buffaloes vaccinated with oil adjuvanted polyvalent FMD vaccine

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R. Sharma

2010-02-01

Full Text Available The present investigation was carried out on 15 randomly selected milch buffaloes divided into three groups on the basis of lactation at an organized farm, to study the foot and mouth disease virus type specific antibodies in milk and serum following FMD vaccination. Milk and serum samples collected before vaccination i.e. 0 day and on 7, 14, 28, 42 and 56 days post vaccination, were analyzed for the detection of FMD virus specific IgG1, IgG2 and IgA antibody response by indirect double antibody sandwich ELISA. Significant FMD virus type specific antibody titres (IgG1, IgG2 and IgA were detected in milk and serum of buffaloes on different days post vaccination, though the levels of antibodies were lower in milk as compared to serum. FMD virus type specific IgG1 was found to be the predominant subclass as compared to IgG2 and IgA both in milk and serum of vaccinated buffaloes. Milk and serum IgG1, IgG2 and IgA antibody titres were positively correlated with values of regression coefficient (R as 0.506, 0.434 and 0.396, respectively.

Human surfactant protein D: SP-D contains a C-type lectin carbohydrate recognition domain.

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Rust, K; Grosso, L; Zhang, V; Chang, D; Persson, A; Longmore, W; Cai, G Z; Crouch, E

1991-10-01

Lung surfactant protein D (SP-D) shows calcium-dependent binding to specific saccharides, and is similar in domain structure to certain members of the calcium-dependent (C-type) lectin family. Using a degenerate oligomeric probe corresponding to a conserved peptide sequence derived from the amino-terminus of the putative carbohydrate binding domain of rat and bovine SP-D, we screened a human lung cDNA library and isolated a 1.4-kb cDNA for the human protein. The relationship of the cDNA to SP-D was established by several techniques including amino-terminal microsequencing of SP-D-derived peptides, and immunoprecipitation of translation products of transcribed mRNA with monospecific antibodies to SP-D. In addition, antibodies to a synthetic peptide derived from a predicted unique epitope within the carbohydrate recognition domain of SP-D specifically reacted with SP-D. DNA sequencing demonstrated a noncollagenous carboxy-terminal domain that is highly homologous with the carboxy-terminal globular domain of previously described C-type lectins. This domain contains all of the so-called "invariant residues," including four conserved cysteine residues, and shows high homology with the mannose-binding subfamily of C-type lectins. Sequencing also demonstrated an amino-terminal collagenous domain that contains an uninterrupted sequence of 59 Gly-X-Y triplets and that also contains the only identified consensus for asparagine-linked oligosaccharides. The studies demonstrate that SP-D is a member of the C-type lectin family, and confirm predicted structural similarities to conglutinin, SP-D, and the serum mannose binding proteins.

Site-specific photoconjugation of antibodies using chemically synthesized IgG-binding domains.

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Perols, Anna; Karlström, Amelie Eriksson

2014-03-19

Site-specific labeling of antibodies can be performed using the immunoglobulin-binding Z domain, derived from staphylococcal protein A (SpA), which has a well-characterized binding site in the Fc region of antibodies. By introducing a photoactivable probe in the Z domain, a covalent bond can be formed between the Z domain and the antibody by irradiation with UV light. The aim of this study was to improve the conjugation yield for labeling of different subclasses of IgG having different sequence composition, using a photoactivated Z domain variant. Four different variants of the Z domain (Z5BPA, Z5BBA, Z32BPA, and Z32BBA) were synthesized to investigate the influence of the position of the photoactivable probe and the presence of a flexible linker between the probe and the protein. For two of the variants, the photoreactive benzophenone group was introduced as part of an amino acid side chain by incorporation of the unnatural amino acid benzoylphenylalanine (BPA) during peptide synthesis. For the other two variants, the photoreactive benzophenone group was attached via a flexible linker by coupling of benzoylbenzoic acid (BBA) to the ε-amino group of a selectively deprotected lysine residue. Photoconjugation experiments using human IgG1, mouse IgG1, and mouse IgG2A demonstrated efficient conjugation for all antibodies. It was shown that differences in linker length had a large impact on the conjugation efficiency for labeling of mouse IgG1, whereas the positioning of the photoactivable probe in the sequence of the protein had a larger effect for mouse IgG2A. Conjugation to human IgG1 was only to a minor extent affected by position or linker length. For each subclass of antibody, the best variant tested using a standard conjugation protocol resulted in conjugation efficiencies of 41-66%, which corresponds to on average approximately one Z domain attached to each antibody. As a combination of the two best performing variants, Z5BBA and Z32BPA, a Z domain variant with

[Expression, crystallization and crystallographic study of the 1st IgV domain of human CD96].

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Jiang, Wenjing; Zhang, Shuijun; Yan, Jinghua; Guo, Ning

2013-05-01

CD96 (Tactile) is an adhesion receptor expressed mainly on activated T cells, NK cells. As a family member of the immunoglobulin-like cell receptor, CD96 consists of three immunoglobulin-like domains (V1, V2/C and C) in the extracellular region. Recent studies have shown that the 1st IgV domain of CD96 (CD96V1) plays an essential role in cell adhesion and NK cell-mediated killing. In this study, the 1st IgV domain of human CD96 (hCD96V1) was cloned and expressed in Escherichia coli (BL21). The soluble protein was obtained by refolding of the hCD96V1 inclusion bodies. From analytical ultracentrifugation, we could predict that CD96 V1 maily exists as dimer with approximate molecular weight of 26.9 kDa. The protein was then successfully crystallized using the sitting-drop vapour-diffusion method. The crystals diffracted to 1.9 angstrom resolution and belonged to space group P21, with unit-cell parameters a = 35.1, b = 69.5, c = 49.6A, alpha=gamma=90 degrees, beta=105.4 degrees.

Association of 5' end neuregulin-1 (NRG1) gene variation with subcortical medial frontal microstructure in humans.

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Winterer, Georg; Konrad, Andreas; Vucurevic, Goran; Musso, Francesco; Stoeter, Peter; Dahmen, Norbert

2008-04-01

Animal data suggest that the gene neuregulin-1 (NRG1) is involved in neuronal myelination. A haplotype (deCODE) in the 5' end region of the gene was described to double the risk for schizophrenia in an Icelandic population (Stefansson, H., Sigurdsson, E., Steinthorsdottir, V., Bjornsdottir, S., Sigmundsson, T., Ghosh, S., Brynjolfsson, J., Gunnarsdottir, S., Ivarsson, O., Chou, T.T., Hjaltason, O., Birgisdottir, B., Jonsson, H., Gudnadottir, V.G., Gudmundsdottir, E., Bjornsson, A., Ingvarsson, B., Ingason, A., Sigfusson, S., Hardardottir, H., Harvey, R.P., Lai, D., Zhou, M., Brunner, D., Mutel, V., Gonzalo, A., Lemke, G., Sainz, J., Johannesson, G., Andresson, T., Gudbjartsson, D., Manolescu, A., Frigge, M.L., Gurney, M.E., Kong, A., Gulcher, J.R., Petursson, H., Stefansson, K. 2002. Neuregulin-1 and susceptibility to schizophrenia. Am. J. Hum. Genet. 71, 877-892). Of note, there is now increasing evidence of disturbed myelination in this illness--particularly in subcortical frontal lobe white matter (Konrad, A., Winterer, G. 2008. Disturbed structural connectivity in schizophrenia--primary factor in pathology or epiphenomenon? Schiz. Bull. [Electronic publication ahead of print]). Therefore, we investigated with diffusion tensor imaging (DTI) the impact of a tagging single nucleotide polymorphism (SNP) from the deCODE haplotype, i.e., SNP8NRG221533, on fractional anisotropy (FA), which reflects structural integrity of white matter. SNP8NRG221533 was selected because it gave the single best uncorrected association with schizophrenia in the original report by Stefansson et al. (Stefansson, H., Sigurdsson, E., Steinthorsdottir, V., Bjornsdottir, S., Sigmundsson, T., Ghosh, S., Brynjolfsson, J., Gunnarsdottir, S., Ivarsson, O., Chou, T.T., Hjaltason, O., Birgisdottir, B., Jonsson, H., Gudnadottir, V.G., Gudmundsdottir, E., Bjornsson, A., Ingvarsson, B., Ingason, A., Sigfusson, S., Hardardottir, H., Harvey, R.P., Lai, D., Zhou, M., Brunner, D., Mutel, V., Gonzalo, A

Working mechanism of immunoglobulin A1 (IgA1) protease: cleavage of IgA1 antibody to Neisseria meningitidis PorA requires de novo synthesis of IgA1 Protease

DEFF Research Database (Denmark)

Vidarsson, G; Overbeeke, N; Stemerding, AM

2005-01-01

Neisseria meningitidis secretes a protease that specifically cleaves the hinge region of immunoglobulin A1 (IgA1), releasing the effector (Fc) domain of IgA1 from the antigen binding (Fab) determinants. Theoretically, the remaining Fab fragments can block pathogen receptors or toxins and still...

Working mechanism of immunoglobulin A1 (IgA1) protease: cleavage of IgA1 antibody to Neisseria meningitidis PorA requires de novo synthesis of IgA1 Protease

NARCIS (Netherlands)

Vidarsson, Gestur; Overbeeke, Natasja; Stemerding, Annette M.; van den Dobbelsteen, Germie; van Ulsen, Peter; van der Ley, Peter; Kilian, Mogens; van de Winkel, Jan G. J.

2005-01-01

Neisseria meningitidis secretes a protease that specifically cleaves the hinge region of immunoglobulin A1 (IgA1), releasing the effector (Fc) domain of IgA1 from the antigen binding (Fab) determinants. Theoretically, the remaining Fab fragments can block pathogen receptors or toxins and still

Recombinant human B7.2 IgV-like domain expressed in bacteria maintains its co-stimulatory activity in vitro.

Science.gov (United States)

Yan, Xiaocai; Ma, Jun; Zheng, Jin; Lai, Baochang; Geng, Yiping; Wang, Yili; Si, Lüsheng

2002-07-01

To investigate which of the two immunoglobulin (Ig)-like domains, the immunoglobulin variable region homologous domain IgV (hB7.2 IgV) and the immunoglobulin constant region homologous domain IgC (hB7.2 IgC) on the human B7.2 molecule contains receptor binding sites, and to evaluate whether the B7.2 protein expressed in bacteria has biological activity in vitro. Three fragments of hB7.2 IgV,hB7.2 IgC and the complete extracellular region of human B7.2 containing both the IgV and IgC domains,hB7.2 Ig (V+C), were amplified by PCR and subcloned into pGEM-Teasy. Three recombinants,pGEX-4T-3-hB7.2 IgV,pGEX-4T-3-hB7.2 IgC and pGEX-4T-3-hB7.2 Ig (V+C), were generated by cloning the fragments into a prokaryote expression plasmid (pGEX-4T-3) and transformed into the host strain E. coli DH5alpha. The relevant target fusion proteins consisting of GST and hB7.2 IgV,hB7.2 IgC and hB7.2 Ig (V+C), were identified by SDS-PAGE and Western blotting. With the presence of the first signal imitated by anti-CD3 antibody, T cell activation was observed by exposing purified T lymphocytes to each soluble form of the three bacterially-produced human B7.2 fusion proteins by [(3)H]-TdR incorporation. Three recombinant fusion proteins of human B7.2, GST-hB7.2 IgV, GST-hB7.2 IgC and GST-hB7.2 Ig (V+C) were produced and detected in inclusion body form from engineered bacteria. With the first signal present,T lymphocytes proliferated when co-stimulated by bacterially-produced either GST-hB7.2 Ig (V+C) or GST-hB7.2 IgV fusion proteins, but not by GST-hB7.2 IgC. Functional human B7.2 fusion protein can be produced in bacteria. The IgV-like domain of human B7.2 is sufficient for B7.2 to interact with its counter-receptors and co-stimulate T lymphocytes.

Presynaptic type III neuregulin1-ErbB signaling targets {alpha}7 nicotinic acetylcholine receptors to axons.

Science.gov (United States)

Hancock, Melissa L; Canetta, Sarah E; Role, Lorna W; Talmage, David A

2008-05-05

Type III Neuregulin1 (Nrg1) isoforms are membrane-tethered proteins capable of participating in bidirectional juxtacrine signaling. Neuronal nicotinic acetylcholine receptors (nAChRs), which can modulate the release of a rich array of neurotransmitters, are differentially targeted to presynaptic sites. We demonstrate that Type III Nrg1 back signaling regulates the surface expression of alpha7 nAChRs along axons of sensory neurons. Stimulation of Type III Nrg1 back signaling induces an increase in axonal surface alpha7 nAChRs, which results from a redistribution of preexisting intracellular pools of alpha7 rather than from increased protein synthesis. We also demonstrate that Type III Nrg1 back signaling activates a phosphatidylinositol 3-kinase signaling pathway and that activation of this pathway is required for the insertion of preexisting alpha7 nAChRs into the axonal plasma membrane. These findings, in conjunction with prior results establishing that Type III Nrg1 back signaling controls gene transcription, demonstrate that Type III Nrg1 back signaling can regulate both short-and long-term changes in neuronal function.

Presynaptic type III neuregulin1-ErbB signaling targets alpha7 nicotinic acetylcholine receptors to axons.

Science.gov (United States)

Hancock, Melissa L; Canetta, Sarah E; Role, Lorna W; Talmage, David A

2008-06-01

Type III Neuregulin1 (Nrg1) isoforms are membrane-tethered proteins capable of participating in bidirectional juxtacrine signaling. Neuronal nicotinic acetylcholine receptors (nAChRs), which can modulate the release of a rich array of neurotransmitters, are differentially targeted to presynaptic sites. We demonstrate that Type III Nrg1 back signaling regulates the surface expression of alpha7 nAChRs along axons of sensory neurons. Stimulation of Type III Nrg1 back signaling induces an increase in axonal surface alpha7 nAChRs, which results from a redistribution of preexisting intracellular pools of alpha7 rather than from increased protein synthesis. We also demonstrate that Type III Nrg1 back signaling activates a phosphatidylinositol 3-kinase signaling pathway and that activation of this pathway is required for the insertion of preexisting alpha7 nAChRs into the axonal plasma membrane. These findings, in conjunction with prior results establishing that Type III Nrg1 back signaling controls gene transcription, demonstrate that Type III Nrg1 back signaling can regulate both short-and long-term changes in neuronal function.

Presynaptic Type III Neuregulin1-ErbB signaling targets α7 nicotinic acetylcholine receptors to axons

Science.gov (United States)

Hancock, Melissa L.; Canetta, Sarah E.; Role, Lorna W.; Talmage, David A.

2008-01-01

Type III Neuregulin1 (Nrg1) isoforms are membrane-tethered proteins capable of participating in bidirectional juxtacrine signaling. Neuronal nicotinic acetylcholine receptors (nAChRs), which can modulate the release of a rich array of neurotransmitters, are differentially targeted to presynaptic sites. We demonstrate that Type III Nrg1 back signaling regulates the surface expression of α7 nAChRs along axons of sensory neurons. Stimulation of Type III Nrg1 back signaling induces an increase in axonal surface α7 nAChRs, which results from a redistribution of preexisting intracellular pools of α7 rather than from increased protein synthesis. We also demonstrate that Type III Nrg1 back signaling activates a phosphatidylinositol 3-kinase signaling pathway and that activation of this pathway is required for the insertion of preexisting α7 nAChRs into the axonal plasma membrane. These findings, in conjunction with prior results establishing that Type III Nrg1 back signaling controls gene transcription, demonstrate that Type III Nrg1 back signaling can regulate both short-and long-term changes in neuronal function. PMID:18458158

The Emerging Importance of IgG Fab Glycosylation in Immunity

NARCIS (Netherlands)

van de Bovenkamp, Fleur S.; Hafkenscheid, Lise; Rispens, Theo; Rombouts, Yoann

2016-01-01

Human IgG is the most abundant glycoprotein in serum and is crucial for protective immunity. In addition to conserved IgG Fc glycans, ∼15-25% of serum IgG contains glycans within the variable domains. These so-called "Fab glycans" are primarily highly processed complex-type biantennary N-glycans

Modular organization of proteins containing C1q-like globular domain.

Science.gov (United States)

Kishore, U; Reid, K B

1999-05-01

The first step in the activation of the classical pathway of complement cascade by immune complexes involves the binding of the six globular heads of C1q to the Fc regions of immunoglobulin G (IgG) or immunoglobulin M (IgM). The globular heads of C1q are located C-terminal to the six triple-helical stalks present in the molecule, each head is considered to be composed of the C-terminal halves (3 x 135 residues) of one A-, one B- and one C-chain. It is not known if the C-terminal globular regions, present in each of the three types of chains, are independently folded modules (with each chain having distinct binding properties towards immunoglobulins) or whether the different binding functions of C1q are dependent upon a globular structure which relies on contributions from all three chains. Recent reports of recombinant production and characterisation of soluble globular head regions of all the three chains indicate that the globular regions of C1q may adopt a modular organization, i.e., each globular head of C1q may be composed of three, structurally and functionally, independent domains, thus retaining multivalency in the form of a heterotrimer. Modules of the same type as the C1q C-terminal module are also found in a variety of noncomplement proteins that include the C-terminal regions of the human type VIII and type X collagens, precerebellin, the chipmunk hibernation proteins, the human endothelial cell protein, multimerin, the serum protein, Acrp-30 which is secreted from mouse adipocytes, and the sunfish inner-ear specific structural protein. The C1q molecule is the only one of these proteins for which, to date, a function has been ascribed to the module. The existence of a shared structural region between C1q and certain collagens may suggest an evolutionarily common ancestral precursor. Various structural and biochemical data suggest that these modules may be responsible for multimerisation through patches of aromatic residues within them.

Cell surface expression of channel catfish leukocyte immune-type receptors (IpLITRs) and recruitment of both Src homology 2 domain-containing protein tyrosine phosphatase (SHP)-1 and SHP-2.

Science.gov (United States)

Montgomery, Benjamin C S; Mewes, Jacqueline; Davidson, Chelsea; Burshtyn, Deborah N; Stafford, James L

2009-04-01

Channel catfish leukocyte immune-type receptors (IpLITRs) are immunoglobulin superfamily (IgSF) members believed to play a role in the control and coordination of cellular immune responses in teleost. Putative stimulatory and inhibitory IpLITRs are co-expressed by different types of catfish immune cells (e.g. NK cells, T cells, B cells, and macrophages) but their signaling potential has not been determined. Following cationic polymer-mediated transfections into human cell lines we examined the surface expression, tyrosine phosphorylation, and phosphatase recruitment potential of two types of putative inhibitory IpLITRs using 'chimeric' expression constructs and an epitope-tagged 'native' IpLITR. We also cloned and expressed the teleost Src homology 2 domain-containing protein tyrosine phosphatases (SHP)-1 and SHP-2 and examined their expression in adult tissues and developing zebrafish embryos. Co-immunoprecipitation experiments support the inhibitory signaling potential of distinct IpLITR-types that bound both SHP-1 and SHP-2 following the phosphorylation of tyrosine residues within their cytoplasmic tail (CYT) regions. Phosphatase recruitment by IpLITRs represents an important first step in understanding their influence on immune cell effector functions and suggests that certain inhibitory signaling pathways are conserved among vertebrates.

Human placenta: relative content of antibodies of different classes and subclasses (IgG1-IgG4) containing lambda- and kappa-light chains and chimeric lambda-kappa-immunoglobulins.

Science.gov (United States)

Lekchnov, Evgenii A; Sedykh, Sergey E; Dmitrenok, Pavel S; Buneva, Valentina N; Nevinsky, Georgy A

2015-06-01

The specific organ placenta is much more than a filter: it is an organ that protects, feeds and regulates the growth of the embryo. Affinity chromatography, ELISA, SDS-PAGE and matrix-assisted laser desorption ionization mass spectrometry were used. Using 10 intact human placentas deprived of blood, a quantitative analysis of average relative content [% of total immunoglobulins (Igs)] was carried out for the first time: (92.7), IgA (2.4), IgM (2.5), kappa-antibodies (51.4), lambda-antibodies (48.6), IgG1 (47.0), IgG2 (39.5), IgG3 (8.8) and IgG4 (4.3). It was shown for the first time that placenta contains sIgA (2.5%). In the classic paradigm, Igs represent products of clonal B-cell populations, each producing antibodies recognizing a single antigen. There is a common belief that IgGs in mammalian biological fluids are monovalent molecules having stable structures and two identical antigen-binding sites. However, similarly to human milk Igs, placenta antibodies undergo extensive half-molecule exchange and the IgG pool consists of 43.5 ± 15.0% kappa-kappa-IgGs and 41.6 ± 17.0% lambda-lambda-IgGs, while 15.0 ± 4.0% of the IgGs contained both kappa- and lambda-light chains. Kappa-kappa-IgGs and lambda-lambda-IgGs contained, respectively (%): IgG1 (47.7 and 34.4), IgG2 (36.3 and 44.5), IgG3 (7.4 and 11.8) and IgG4 (7.5 and 9.1), while chimeric kappa-lambda-IgGs consisted of (%): 43.5 IgG1, 41.0 IgG2, 5.6 IgG3 and 7.9 IgG4. Our data are indicative of the possibility of half-molecule exchange between placenta IgGs of various subclasses, raised against different antigens, which explains a very well-known polyspecificity and cross-reactivity of different human IgGs. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The IgV domain of human B7-2 (CD86) is sufficient to co-stimulate T lymphocytes and induce cytokine secretion.

Science.gov (United States)

Rennert, P; Furlong, K; Jellis, C; Greenfield, E; Freeman, G J; Ueda, Y; Levine, B; June, C H; Gray, G S

1997-06-01

B7-1 (CD80) and B7-2 (CD86) are genetically and structurally related molecules expressed on antigen-presenting cells. Both bind CD28 to co-stimulate T lymphocytes, resulting in proliferation and cytokine production. The extracellular portions of B7-1 and B7-2 which bind to CD28 and CTLA-4 are related to Ig variable (V) and Ig constant (C) domain sequences. Recent reports have described splice variant forms of B7 proteins which occur in vivo and are of unknown function. Here we describe soluble recombinant forms of B7-1 and B7-2 containing either both of the Ig-like extracellular domains or the individual IgV or IgC domains coupled to an Ig Fc tail. Soluble B7-1 and B7-2 bind to CD28 and CTLA-4, and effectively co-stimulate T lymphocytes resulting in their proliferation and the secretion of cytokines. Furthermore, the IgV domain of B7-2 binds CD28 and CTLA-4, competes with B7-1 and B7-2 for binding to these receptors, and co-stimulates T lymphocytes. Cross-linked soluble B7-2v was the most potent co-stimulatory molecule tested and was active at a concentration approximately 100-fold lower than cross-linked soluble B7-1 or B7-2 proteins. When bound to tosyl-activated beads, B7-2v was capable of sustaining multiple rounds of T cell expansion. These data complement the description of naturally occurring variants to suggest that T cell co-stimulation in vivo may be regulated by soluble or truncated forms of B7 proteins.

Importance of neonatal FcR in regulating the serum half-life of therapeutic proteins containing the Fc domain of human IgG1: a comparative study of the affinity of monoclonal antibodies and Fc-fusion proteins to human neonatal FcR.

Science.gov (United States)

Suzuki, Takuo; Ishii-Watabe, Akiko; Tada, Minoru; Kobayashi, Tetsu; Kanayasu-Toyoda, Toshie; Kawanishi, Toru; Yamaguchi, Teruhide

2010-02-15

The neonatal FcR (FcRn) binds to the Fc domain of IgG at acidic pH in the endosome and protects IgG from degradation, thereby contributing to the long serum half-life of IgG. To date, more than 20 mAb products and 5 Fc-fusion protein products have received marketing authorization approval in the United States, the European Union, or Japan. Many of these therapeutic proteins have the Fc domain of human IgG1; however, the serum half-lives differ in each protein. To elucidate the role of FcRn in the pharmacokinetics of Fc domain-containing therapeutic proteins, we evaluated the affinity of the clinically used human, humanized, chimeric, or mouse mAbs and Fc-fusion proteins to recombinant human FcRn by surface plasmon resonance analysis. The affinities of these therapeutic proteins to FcRn were found to be closely correlated with the serum half-lives reported from clinical studies, suggesting the important role of FcRn in regulating their serum half-lives. The relatively short serum half-life of Fc-fusion proteins was thought to arise from the low affinity to FcRn. The existence of some mAbs having high affinity to FcRn and a short serum half-life, however, suggested the involvement of other critical factor(s) in determining the serum half-life of such Abs. We further investigated the reason for the relatively low affinity of Fc-fusion proteins to FcRn and suggested the possibility that the receptor domain of Fc-fusion protein influences the structural environment of the FcRn binding region but not of the FcgammaRI binding region of the Fc domain.

Induction of a Th-1-biased IgG subclass response against equine herpesvirus type 1 in horses previously infected with type 4 virus.

Science.gov (United States)

Bannai, Hiroshi; Tsujimura, Koji; Kondo, Takashi; Nemoto, Manabu; Yamanaka, Takashi; Sugiura, Takeo; Maeda, Ken; Matsumura, Tomio

2011-04-01

An immunoglobulin G (IgG) subclass response against equine herpesvirus type 1 (EHV-1) infection was investigated in horses that were naïve to EHV-1/4 and those that had previously been exposed to EHV-4. The IgG subclass response was determined by an ELISA using EHV-1-specific recombinant gG protein as an antigen. In most horses naïve to EHV-1/4, IgGa, IgGb, and IgG(T) were induced after experimental infection with EHV-1. In contrast, a subclass response dominated by IgGa and IgGb, with no apparent increase in IgG(T), was observed after EHV-1 infection in horses previously infected with EHV-4. Horses naturally infected with EHV-1 in the field showed similar responses. These results indicated that pre-infection with EHV-4 induced a Th-1-biased IgG subclass response against subsequent EHV-1 infection.

[Family of ribosomal proteins S1 contains unique conservative domain].

Science.gov (United States)

Deriusheva, E I; Machulin, A V; Selivanova, O M; Serdiuk, I N

2010-01-01

Different representatives of bacteria have different number of amino acid residues in the ribosomal proteins S1. This number varies from 111 (Spiroplasma kunkelii) to 863 a.a. (Treponema pallidum). Traditionally and for lack of this protein three-dimensional structure, its architecture is represented as repeating S1 domains. Number of these domains depends on the protein's length. Domain's quantity and its boundaries data are contained in the specialized databases, such as SMART, Pfam and PROSITE. However, for the same object these data may be very different. For search of domain's quantity and its boundaries, new approach, based on the analysis of dicted secondary structure (PsiPred), was used. This approach allowed us to reveal structural domains in amino acid sequences of S1 proteins and at that number varied from one to six. Alignment of S1 proteins, containing different domain's number, with the S1 RNAbinding domain of Escherichia coli PNPase elicited a fact that in family of ribosomal proteins SI one domain has maximal homology with S1 domain from PNPase. This conservative domain migrates along polypeptide chain and locates in proteins, containing different domain's number, according to specified pattern. In this domain as well in the S1 domain from PNPase, residues Phe-19, Phe-22, His-34, Asp-64 and Arg-68 are clustered on the surface and formed RNA binding site.

Characterization of Human and Murine T-Cell Immunoglobulin Mucin Domain 4 (TIM-4) IgV Domain Residues Critical for Ebola Virus Entry.

Science.gov (United States)

Rhein, Bethany A; Brouillette, Rachel B; Schaack, Grace A; Chiorini, John A; Maury, Wendy

2016-07-01

Phosphatidylserine (PtdSer) receptors that are responsible for the clearance of dying cells have recently been found to mediate enveloped virus entry. Ebola virus (EBOV), a member of the Filoviridae family of viruses, utilizes PtdSer receptors for entry into target cells. The PtdSer receptors human and murine T-cell immunoglobulin mucin (TIM) domain proteins TIM-1 and TIM-4 mediate filovirus entry by binding to PtdSer on the virion surface via a conserved PtdSer binding pocket within the amino-terminal IgV domain. While the residues within the TIM-1 IgV domain that are important for EBOV entry are characterized, the molecular details of virion-TIM-4 interactions have yet to be investigated. As sequences and structural alignments of the TIM proteins suggest distinct differences in the TIM-1 and TIM-4 IgV domain structures, we sought to characterize TIM-4 IgV domain residues required for EBOV entry. Using vesicular stomatitis virus pseudovirions bearing EBOV glycoprotein (EBOV GP/VSVΔG), we evaluated virus binding and entry into cells expressing TIM-4 molecules mutated within the IgV domain, allowing us to identify residues important for entry. Similar to TIM-1, residues in the PtdSer binding pocket of murine and human TIM-4 (mTIM-4 and hTIM-4) were found to be important for EBOV entry. However, additional TIM-4-specific residues were also found to impact EBOV entry, with a total of 8 mTIM-4 and 14 hTIM-4 IgV domain residues being critical for virion binding and internalization. Together, these findings provide a greater understanding of the interaction of TIM-4 with EBOV virions. With more than 28,000 cases and over 11,000 deaths during the largest and most recent Ebola virus (EBOV) outbreak, there has been increased emphasis on the development of therapeutics against filoviruses. Many therapies under investigation target EBOV cell entry. T-cell immunoglobulin mucin (TIM) domain proteins are cell surface factors important for the entry of many enveloped viruses

βig-h3 Represses T-Cell Activation in Type 1 Diabetes.

Science.gov (United States)

Patry, Maeva; Teinturier, Romain; Goehrig, Delphine; Zetu, Cornelia; Ripoche, Doriane; Kim, In-San; Bertolino, Philippe; Hennino, Ana

2015-12-01

βig-h3/TGF-βi is a secreted protein capable of binding to both extracellular matrix and cells. Human genetic studies recently revealed that in the tgfbi gene encoding for βig-h3, three single nucleotide polymorphisms were significantly associated with type 1 diabetes (T1D) risk. Pancreatic islets express βig-h3 in physiological conditions, but this expression is reduced in β-cell insult in T1D. Since the integrity of islets is destroyed by autoimmune T lymphocytes, we thought to investigate the impact of βig-h3 on T-cell activation. We show here that βig-h3 inhibits T-cell activation markers as well as cytotoxic molecule production as granzyme B and IFN-γ. Furthermore, βig-h3 inhibits early T-cell receptor signaling by repressing the activation of the early kinase protein Lck. Moreover, βig-h3-treated T cells are unable to induce T1D upon transfer in Rag2 knockout mice. Our study demonstrates for the first time that T-cell activation is modulated by βig-h3, an islet extracellular protein, in order to efficiently avoid autoimmune response. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Mutations in type 3 reovirus that determine binding to sialic acid are contained in the fibrous tail domain of viral attachment protein sigma1.

Science.gov (United States)

Chappell, J D; Gunn, V L; Wetzel, J D; Baer, G S; Dermody, T S

1997-03-01

The reovirus attachment protein, sigma1, determines numerous aspects of reovirus-induced disease, including viral virulence, pathways of spread, and tropism for certain types of cells in the central nervous system. The sigma1 protein projects from the virion surface and consists of two distinct morphologic domains, a virion-distal globular domain known as the head and an elongated fibrous domain, termed the tail, which is anchored into the virion capsid. To better understand structure-function relationships of sigma1 protein, we conducted experiments to identify sequences in sigma1 important for viral binding to sialic acid, a component of the receptor for type 3 reovirus. Three serotype 3 reovirus strains incapable of binding sialylated receptors were adapted to growth in murine erythroleukemia (MEL) cells, in which sialic acid is essential for reovirus infectivity. MEL-adapted (MA) mutant viruses isolated by serial passage in MEL cells acquired the capacity to bind sialic acid-containing receptors and demonstrated a dependence on sialic acid for infection of MEL cells. Analysis of reassortant viruses isolated from crosses of an MA mutant virus and a reovirus strain that does not bind sialic acid indicated that the sigma1 protein is solely responsible for efficient growth of MA mutant viruses in MEL cells. The deduced sigma1 amino acid sequences of the MA mutant viruses revealed that each strain contains a substitution within a short region of sequence in the sigma1 tail predicted to form beta-sheet. These studies identify specific sequences that determine the capacity of reovirus to bind sialylated receptors and suggest a location for a sialic acid-binding domain. Furthermore, the results support a model in which type 3 sigma1 protein contains discrete receptor binding domains, one in the head and another in the tail that binds sialic acid.

Crystal structure of the second fibronectin type III (FN3) domain from human collagen α1 type XX.

Science.gov (United States)

Zhao, Jingfeng; Ren, Jixia; Wang, Nan; Cheng, Zhong; Yang, Runmei; Lin, Gen; Guo, Yi; Cai, Dayong; Xie, Yong; Zhao, Xiaohong

2017-12-01

Collagen α1 type XX, which contains fibronectin type III (FN3) repeats involving six FN3 domains (referred to as the FN#1-FN#6 domains), is an unusual member of the fibril-associated collagens with interrupted triple helices (FACIT) subfamily of collagens. The results of standard protein BLAST suggest that the FN3 repeats might contribute to collagen α1 type XX acting as a cytokine receptor. To date, solution NMR structures of the FN#3, FN#4 and FN#6 domains have been determined. To obtain further structural evidence to understand the relationship between the structure and function of the FN3 repeats from collagen α1 type XX, the crystal structure of the FN#2 domain from human collagen α1 type XX (residues Pro386-Pro466; referred to as FN2-HCXX) was solved at 2.5 Å resolution. The crystal structure of FN2-HCXX shows an immunoglobulin-like fold containing a β-sandwich structure, which is formed by a three-stranded β-sheet (β1, β2 and β5) packed onto a four-stranded β-sheet (β3, β4, β6 and β7). Two consensus domains, tencon and fibcon, are structural analogues of FN2-HCXX. Fn8, an FN3 domain from human oncofoetal fibronectin, is the closest structural analogue of FN2-HCXX derived from a naturally occurring sequence. Based solely on the structural similarity of FN2-HCXX to other FN3 domains, the detailed functions of FN2-HCXX and the FN3 repeats in collagen α1 type XX cannot be identified.

Maturation of Shark Single-Domain (IgNAR) Antibodies: Evidence for Induced-Fit Binding

Energy Technology Data Exchange (ETDEWEB)

Stanfield, R.L.; Dooley, H.; Verdino, P.; Flajnik, M.F.; Wilson, I.A.; /Scripps Res. Inst. /Maryland U.

2007-07-13

Sharks express an unusual heavy-chain isotype called IgNAR, whose variable regions bind antigen as independent soluble domains. To further probe affinity maturation of the IgNAR response, we structurally characterized the germline and somatically matured versions of a type II variable (V) region, both in the presence and absence of its antigen, hen egg-white lysozyme. Despite a disulfide bond linking complementarity determining regions (CDRs) 1 and 3, both germline and somatically matured V regions displayed significant structural changes in these CDRs upon complex formation with antigen. Somatic mutations in the IgNAR V region serve to increase the number of contacts with antigen, as reflected by a tenfold increase in affinity, and one of these mutations appears to stabilize the CDR3 region. In addition, a residue in the HV4 loop plays an important role in antibody-antigen interaction, consistent with the high rate of somatic mutations in this non-CDR loop.

Identification of carbohydrate-binding domains in the attachment proteins of type 1 and type 3 reoviruses.

Science.gov (United States)

Chappell, J D; Duong, J L; Wright, B W; Dermody, T S

2000-09-01

The reovirus attachment protein, sigma1, is responsible for strain-specific patterns of viral tropism in the murine central nervous system and receptor binding on cultured cells. The sigma1 protein consists of a fibrous tail domain proximal to the virion surface and a virion-distal globular head domain. To better understand mechanisms of reovirus attachment to cells, we conducted studies to identify the region of sigma1 that binds cell surface carbohydrate. Chimeric and truncated sigma1 proteins derived from prototype reovirus strains type 1 Lang (T1L) and type 3 Dearing (T3D) were expressed in insect cells by using a baculovirus vector. Assessment of expressed protein susceptibility to proteolytic cleavage, binding to anti-sigma1 antibodies, and oligomerization indicates that the chimeric and truncated sigma1 proteins are properly folded. To assess carbohydrate binding, recombinant sigma1 proteins were tested for the capacity to agglutinate mammalian erythrocytes and to bind sialic acid presented on glycophorin, the cell surface molecule bound by type 3 reovirus on human erythrocytes. Using a panel of two wild-type and ten chimeric and truncated sigma1 proteins, the sialic acid-binding domain of type 3 sigma1 was mapped to a region of sequence proposed to form the more amino terminal of two predicted beta-sheet structures in the tail. This unit corresponds to morphologic region T(iii) observed in computer-processed electron micrographs of sigma1 protein purified from virions. In contrast, the homologous region of T1L sigma1 sequence was not implicated in carbohydrate binding; rather, sequences in the distal portion of the tail known as the neck were required. Results of these studies demonstrate that a functional receptor-binding domain, which uses sialic acid as its ligand, is contained within morphologic region T(iii) of the type 3 sigma1 tail. Furthermore, our findings indicate that T1L and T3D sigma1 proteins contain different arrangements of receptor

Efficient subgroup C avian sarcoma and leukosis virus receptor activity requires the IgV domain of the Tvc receptor and proper display on the cell membrane.

Science.gov (United States)

Munguia, Audelia; Federspiel, Mark J

2008-11-01

We recently identified and cloned the receptor for subgroup C avian sarcoma and leukosis viruses [ASLV(C)], i.e., Tvc, a protein most closely related to mammalian butyrophilins, which are members of the immunoglobulin protein family. The extracellular domain of Tvc contains two immunoglobulin-like domains, IgV and IgC, which presumably each contain a disulfide bond important for native function of the protein. In this study, we have begun to identify the functional determinants of Tvc responsible for ASLV(C) receptor activity. We found that the IgV domain of the Tvc receptor is responsible for interacting with the glycoprotein of ASLV(C). Additional experiments demonstrated that a domain was necessary as a spacer between the IgV domain and the membrane-spanning domain for efficient Tvc receptor activity, most likely to orient the IgV domain a proper distance from the cell membrane. The effects on ASLV(C) glycoprotein binding and infection efficiency were also studied by site-directed mutagenesis of the cysteine residues of Tvc as well as conserved amino acid residues of the IgV Tvc domain compared to other IgV domains. In this initial analysis of Tvc determinants important for interacting with ASLV(C) glycoproteins, at least two aromatic amino acid residues in the IgV domain of Tvc, Trp-48 and Tyr-105, were identified as critical for efficient ASLV(C) infection. Interestingly, one or more aromatic amino acid residues have been identified as critical determinants in the other ASLV(A-E) receptors for a proper interaction with ASLV glycoproteins. This suggests that the ASLV glycoproteins may share a common mechanism of receptor interaction with an aromatic residue(s) on the receptor critical for triggering conformational changes in SU that initiate the fusion process required for efficient virus infection.

Efficient Subgroup C Avian Sarcoma and Leukosis Virus Receptor Activity Requires the IgV Domain of the Tvc Receptor and Proper Display on the Cell Membrane▿

Science.gov (United States)

Munguia, Audelia; Federspiel, Mark J.

2008-01-01

We recently identified and cloned the receptor for subgroup C avian sarcoma and leukosis viruses [ASLV(C)], i.e., Tvc, a protein most closely related to mammalian butyrophilins, which are members of the immunoglobulin protein family. The extracellular domain of Tvc contains two immunoglobulin-like domains, IgV and IgC, which presumably each contain a disulfide bond important for native function of the protein. In this study, we have begun to identify the functional determinants of Tvc responsible for ASLV(C) receptor activity. We found that the IgV domain of the Tvc receptor is responsible for interacting with the glycoprotein of ASLV(C). Additional experiments demonstrated that a domain was necessary as a spacer between the IgV domain and the membrane-spanning domain for efficient Tvc receptor activity, most likely to orient the IgV domain a proper distance from the cell membrane. The effects on ASLV(C) glycoprotein binding and infection efficiency were also studied by site-directed mutagenesis of the cysteine residues of Tvc as well as conserved amino acid residues of the IgV Tvc domain compared to other IgV domains. In this initial analysis of Tvc determinants important for interacting with ASLV(C) glycoproteins, at least two aromatic amino acid residues in the IgV domain of Tvc, Trp-48 and Tyr-105, were identified as critical for efficient ASLV(C) infection. Interestingly, one or more aromatic amino acid residues have been identified as critical determinants in the other ASLV(A-E) receptors for a proper interaction with ASLV glycoproteins. This suggests that the ASLV glycoproteins may share a common mechanism of receptor interaction with an aromatic residue(s) on the receptor critical for triggering conformational changes in SU that initiate the fusion process required for efficient virus infection. PMID:18768966

IgA Nephropathy and Henoch-Schoenlein Purpura Nephritis: Aberrant Glycosylation of IgA1, Formation of IgA1-Containing Immune Complexes, and Activation of Mesangial Cells

DEFF Research Database (Denmark)

Novak, J.; Moldoveanu, Z.; Renfrow, M.B.

2007-01-01

IgA1 in the circulation and glomerular deposits of patients with IgA nephropathy (IgAN) is aberrantly glycosylated; the hinge-region O-linked glycans are galactose-deficient. The circulating IgA1 of patients with Henoch-Schoenlein purpura nephritis (HSPN) has a similar defect. This aberrancy...

Identification of distinct glycoforms of IgA1 in plasma from patients with IgA nephropathy and healthy individuals

DEFF Research Database (Denmark)

Lehoux, Sylvain; Mi, Rongjuan; Aryal, Rajindra P

2014-01-01

Immunoglobulin A nephropathy (IgAN) is the most common form of glomerulonephritis worldwide and is histologically characterized by the deposition of IgA1 and consequent inflammation in the glomerular mesangium. Prior studies suggested that serum IgA1 from IgAN patients contains aberrant, undergal......Immunoglobulin A nephropathy (IgAN) is the most common form of glomerulonephritis worldwide and is histologically characterized by the deposition of IgA1 and consequent inflammation in the glomerular mesangium. Prior studies suggested that serum IgA1 from IgAN patients contains aberrant...... there are different glycoforms of IgA1 in plasma from patients with IgAN and healthy individuals. While total plasma IgA in IgAN patients was elevated ~1.6-fold compared to that in healthy donors, IgA1 in all samples was unexpectedly separable into two distinct glycoforms: one with core 1 based O......-glycans, and the other exclusively containing Tn/STn structures. Importantly, Tn antigen present on IgA1 from IgAN patients and controls was convertible into the core 1 structure in vitro by recombinant T-synthase. Our results demonstrate that undergalactosylation of O-glycans in IgA1 is not restricted to Ig...

Alterations in Fibronectin Type III Domain Containing 1 Protein Gene Are Associated with Hypertension.

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Alan Y Deng

Full Text Available Multiple quantitative trait loci (QTLs for blood pressure (BP have been detected in rat models of human polygenic hypertension. Great challenges confronting us include molecular identifications of individual QTLs. We first defined the chromosome region harboring C1QTL1 to a segment of 1.9 megabases that carries 9 genes. Among them, we identified the gene encoding the fibronectin type III domain containing 1 protein (Fndc1/activator of G protein signaling 8 (Ags8 to be the strongest candidate for C1QTL1, since numerous non-synonymous mutations are found. Moreover, the 5' Fndc1/Ags8 putative promoter contains numerous mutations that can account for its differential expression in kidneys and the heart, prominent organs in modulating BP, although the Fndc1/Ags8 protein was not detectable in these organs under our experimental conditions. This work has provided the premier evidence that Fndc1/Ags8 is a novel and strongest candidate gene for C1QTL1 without completely excluding other 8 genes in the C1QTL1-residing interval. If proven true by future in vivo function studies such as single-gene Fndc1/Ags8 congenics, transgenesis or targeted-gene modifications, it might represent a part of the BP genetic architecture that operates in the upstream position distant from the end-phase physiology of BP control, since it activates a Gbetagamma component in a signaling pathway. Its functional role could validate the concept that a QTL in itself can influence BP 'indirectly' by regulating other genes downstream in a pathway. The elucidation of the mechanisms initiated by Fndc/Ags8 variations will reveal novel insights into the BP modulation via a regulatory hierarchy.

Association between IgE-mediated allergies and diabetes mellitus type 1 in children and adolescents.

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Klamt, Sabine; Vogel, Mandy; Kapellen, Thomas M; Hiemisch, Andreas; Prenzel, Freerk; Zachariae, Silke; Ceglarek, Uta; Thiery, Joachim; Kiess, Wieland

2015-11-01

Type 1 diabetes mellitus (T1DM) is characterized by an immunological reaction that is dominated by type-1 T helper (Th1) cells, whereas immunoglobulin E (IgE)-mediated allergies are associated with Th2 cell. According to the Th1/Th2-hypothesis, the immune system is said to either develop into the direction of Th1 or Th2 cells. This would mean that a child developing T1DM is unlikely to develop an IgE-mediated allergy and vice versa. The aim of the study was to investigate the association between the prevalence of T1DM and IgE-mediated allergies. We designed a prospective case control study with 94 children and adolescents with T1DM and 188 age- and sex-matched control children. The basis of our investigations was a questionnaire concerning the family and children's history as to the presence of IgE-mediated allergies. Moreover, the following blood investigations were done: total serum IgE, specific IgE antibodies to major inhalant allergens, and a multiplex cytokine analysis measuring levels of specific cytokines representing either Th1- or Th2- cytokines. Children with T1DM reported the presence of IgE-mediated allergies significantly more often than children of the control group. Children with T1DM had significantly higher tumor necrosis factor alpha (TNFα) levels than healthy controls. Levels of interleukin-2 (IL-2) and IL-6 were higher in the groups of children with the presence of a personal history of allergies, regardless of the presence of T1DM. Our results suggest that T1DM is associated with a higher risk of a self-reported presence of IgE-mediated allergies and that the Th1/Th2-hypothesis may be an oversimplification. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The NRG1 exon 11 missense variant is not associated with autism in the Central Valley of Costa Rica

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Fallas Marietha

2007-05-01

Full Text Available Abstract Background We are conducting a genetic study of autism in the isolated population of the Central Valley of Costa Rica (CVCR. A novel Neuregulin 1 (NRG1 missense variant (exon 11 G>T was recently associated with psychosis and schizophrenia (SCZ in the same population isolate. Methods We genotyped the NRG1 exon 11 missense variant in 146 cases with autism, or autism spectrum disorder, with CVCR ancestry, and both parents when available (N = 267 parents from 143 independent families. Additional microsatellites were genotyped to examine haplotypes bearing the exon 11 variant. Results The NRG1 exon 11 G>T variant was found in 4/146 cases including one de novo occurrence. The frequency of the variant in case chromosomes was 0.014 and 0.045 in the parental non-transmitted chromosomes. At least 6 haplotypes extending 0.229 Mb were associated with the T allele. Three independent individuals, with no personal or family history of psychiatric disorder, shared at least a 1 megabase haplotype 5' to the T allele. Conclusion The NRG1 exon 11 missense variant is not associated with autism in the CVCR.

CD80 and CD86 IgC domains are important for quaternary structure, receptor binding and co-signaling function.

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Girard, Tanya; Gaucher, Denis; El-Far, Mohamed; Breton, Gaëlle; Sékaly, Rafick-Pierre

2014-09-01

CD86 and CD80, the ligands for the co-stimulatory molecules CD28 and CTLA-4, are members of the Ig superfamily. Their structure includes Ig variable-like (IgV) domains, Ig constant-like (IgC) domains and intracellular domains. Although crystallographic studies have clearly identified the IgV domain to be responsible for receptor interactions, earlier studies suggested that both Ig domains are required for full co-signaling function. Herein, we have used deletion and chimeric human CD80 and CD86 molecules in co-stimulation assays to study the impact of the multimeric state of IgV and IgC domains on receptor binding properties and on co-stimulatory function in a peptide-specific T cell activation model. We report for the first time the presence of CD80 dimers and CD86 monomers in living cells. Moreover, we show that the IgC domain of both molecules inhibits multimer formation and greatly affects binding to the co-receptors CD28 and CTLA-4. Finally, both IgC and intracellular domains are required for full co-signaling function. These findings reveal the distinct but complementary roles of CD80 and CD86 IgV and IgC domains in T cell activation. Copyright © 2014 Elsevier B.V. All rights reserved.

Cellular Signaling and Production of Galactose-Deficient IgA1 in IgA Nephropathy, an Autoimmune Disease

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Colin Reily

2014-01-01

Full Text Available Immunoglobulin A (IgA nephropathy (IgAN, the leading cause of primary glomerulonephritis, is characterized by IgA1-containing immunodeposits in the glomeruli. IgAN is a chronic disease, with up to 40% of patients progressing to end-stage renal disease, with no disease-specific treatment. Multiple studies of the origin of the glomerular immunodeposits have linked elevated circulating levels of aberrantly glycosylated IgA1 (galactose-deficient in some O-glycans; Gd-IgA1 with formation of nephritogenic Gd-IgA1-containing immune complexes. Gd-IgA1 is recognized as an autoantigen in susceptible individuals by anti-glycan autoantibodies, resulting in immune complexes that may ultimately deposit in the kidney and induce glomerular injury. Genetic studies have revealed that an elevated level of Gd-IgA1 in the circulation of IgAN patients is a hereditable trait. Moreover, recent genome-wide association studies have identified several immunity-related loci that associated with IgAN. Production of Gd-IgA1 by IgA1-secreting cells of IgAN patients has been attributed to abnormal expression and activity of several key glycosyltransferases. Substantial evidence is emerging that abnormal signaling in IgA1-producing cells is related to the production of Gd-IgA1. As Gd-IgA1 is the key autoantigen in IgAN, understanding the genetic, biochemical, and environmental aspects of the abnormal signaling in IgA1-producing cells will provide insight into possible targets for future disease-specific therapy.

Diverse oligomeric states of CEACAM IgV domains.

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Bonsor, Daniel A; Günther, Sebastian; Beadenkopf, Robert; Beckett, Dorothy; Sundberg, Eric J

2015-11-03

Carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) comprise a large family of cell surface adhesion molecules that bind to themselves and other family members to carry out numerous cellular functions, including proliferation, signaling, differentiation, tumor suppression, and survival. They also play diverse and significant roles in immunity and infection. The formation of CEACAM oligomers is caused predominantly by interactions between their N-terminal IgV domains. Although X-ray crystal structures of CEACAM IgV domain homodimers have been described, how CEACAMs form heterodimers or remain monomers is poorly understood. To address this key aspect of CEACAM function, we determined the crystal structures of IgV domains that form a homodimeric CEACAM6 complex, monomeric CEACAM8, and a heterodimeric CEACAM6-CEACAM8 complex. To confirm and quantify these interactions in solution, we used analytical ultracentrifugation to measure the dimerization constants of CEACAM homodimers and isothermal titration calorimetry to determine the thermodynamic parameters and binding affinities of CEACAM heterodimers. We found the CEACAM6-CEACAM8 heterodimeric state to be substantially favored energetically relative to the CEACAM6 homodimer. Our data provide a molecular basis for the adoption of the diverse oligomeric states known to exist for CEACAMs and suggest ways in which CEACAM6 and CEACAM8 regulate the biological functions of one another, as well as of additional CEACAMs with which they interact, both in cis and in trans.

The Drosophila cell adhesion molecule Neuroglian regulates Lissencephaly-1 localisation in circulating immunosurveillance cells

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Williams Michael J

2009-03-01

Full Text Available Abstract Background When the parasitoid wasp Leptopilina boulardi lays its eggs in Drosophila larvae phagocytic cells called plasmatocytes and specialized cells known as lamellocytes encapsulate the egg. This requires these circulating immunosurveillance cells (haemocytes to change from a non-adhesive to an adhesive state enabling them to bind to the invader. Interestingly, attachment of leukocytes, platelets, and insect haemocytes requires the same adhesion complexes as epithelial and neuronal cells. Results Here evidence is presented showing that the Drosophila L1-type cell adhesion molecule Neuroglian (Nrg is required for haemocytes to encapsulate L. boulardi wasp eggs. The amino acid sequence FIGQY containing a conserved phosphorylated tyrosine is found in the intracellular domain of all L1-type cell adhesion molecules. This conserved tyrosine is phosphorylated at the cell periphery of plasmatocytes and lamellocytes prior to parasitisation, but dephosphorylated after immune activation. Intriguingly, another pool of Nrg located near the nucleus of plasmatocytes remains phosphorylated after parasitisation. In mammalian neuronal cells phosphorylated neurofascin, another L1-type cell adhesion molecule interacts with a nucleokinesis complex containing the microtubule binding protein lissencephaly-1 (Lis1 1. Interestingly in plasmatocytes from Nrg mutants the nucleokinesis regulating protein Lissencephaly-1 (Lis1 fails to localise properly around the nucleus and is instead found diffuse throughout the cytoplasm and at unidentified perinuclear structures. After attaching to the wasp egg control plasmatocytes extend filopodia laterally from their cell periphery; as well as extending lateral filopodia plasmatocytes from Nrg mutants also extend many filopodia from their apical surface. Conclusion The Drosophila cellular adhesion molecule Neuroglian is expressed in haemocytes and its activity is required for the encapsulation of L. boularli eggs. At

Efficient Subgroup C Avian Sarcoma and Leukosis Virus Receptor Activity Requires the IgV Domain of the Tvc Receptor and Proper Display on the Cell Membrane▿

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Munguia, Audelia; Federspiel, Mark J.

2008-01-01

We recently identified and cloned the receptor for subgroup C avian sarcoma and leukosis viruses [ASLV(C)], i.e., Tvc, a protein most closely related to mammalian butyrophilins, which are members of the immunoglobulin protein family. The extracellular domain of Tvc contains two immunoglobulin-like domains, IgV and IgC, which presumably each contain a disulfide bond important for native function of the protein. In this study, we have begun to identify the functional determinants of Tvc respons...

Functional Elements on SIRPα IgV domain Mediate Cell Surface Binding to CD47

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Liu, Yuan; Tong, Qiao; Zhou, Yubin; Lee, Hsiau-Wei; Yang, Jenny J.; Bühring, Hans-Jörg; Chen, Yi-Tien; Ha, Binh; Chen, Celia X-J.; Zen, Ke

2007-01-01

Summary SIRPα and SIRPβ1, the two major isoforms of the signal regulatory protein (SIRP) family, are co-expressed in human leukocytes but mediate distinct extracellular binding interactions and divergent cell signaling responses. Previous studies have demonstrated that binding of SIRPα with CD47, another important cell surface molecule, through the extracellular IgV domain regulates important leukocyte functions including macrophage recognition, leukocyte adhesion and transmigration. Although SIRPβ1 shares highly homologous extracellular IgV structure with SIRPα, it does not bind to CD47. In this study, we defined key amino acid residues exclusively expressing in the IgV domain of SIRPα, but not SIRPβ1, which determine the extracellular binding interaction of SIRPα to CD47. These key residues include Gln67, a small hydrophobic amino acid (Ala or Val) at the 57th position and Met102. We found that Gln67 and Ala/Val57 are critical. Mutation of either of these residues abates SIRPα directly binding to CD47. Functional cell adhesion and leukocyte transmigration assays further demonstrated central roles of Gln67 and Ala/Val57 in SIRPα extracellular binding mediated cell interactions and cell migration. Another SIRPα-specific residue, Met102, appears to assist SIRPα IgV binding through Gln67 and Ala/Val57. An essential role of these amino acids in SIRPα binding to CD47 was further confirmed by introducing these residues into the SIRPβ1 IgV domain, which dramatically converts SIRPβ1 into a CD47-binding molecule. Our results thus revealed the molecular basis by which SIRPα selectively binds to CD47 and shed new light into the structural mechanisms of SIRP isoform mediated distinctive extracellular interactions and cellular responses. PMID:17070842

Functional elements on SIRPalpha IgV domain mediate cell surface binding to CD47.

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Liu, Yuan; Tong, Qiao; Zhou, Yubin; Lee, Hsiau-Wei; Yang, Jenny J; Bühring, Hans-Jörg; Chen, Yi-Tien; Ha, Binh; Chen, Celia X-J; Yang, Yang; Zen, Ke

2007-01-19

SIRPalpha and SIRPbeta1, the two major isoforms of the signal regulatory protein (SIRP) family, are co-expressed in human leukocytes but mediate distinct extracellular binding interactions and divergent cell signaling responses. Previous studies have demonstrated that binding of SIRPalpha with CD47, another important cell surface molecule, through the extracellular IgV domain regulates important leukocyte functions including macrophage recognition, leukocyte adhesion and transmigration. Although SIRPbeta1 shares highly homologous extracellular IgV structure with SIRPalpha, it does not bind to CD47. Here, we defined key amino acid residues exclusively expressing in the IgV domain of SIRPalpha, but not SIRPbeta1, which determine the extracellular binding interaction of SIRPalpha to CD47. These key residues include Gln67, a small hydrophobic amino acid (Ala or Val) at the 57th position and Met102. We found that Gln67 and Ala/Val57 are critical. Mutation of either of these residues abates SIRPalpha directly binding to CD47. Functional cell adhesion and leukocyte transmigration assays further demonstrated central roles of Gln67 and Ala/Val57 in SIRPalpha extracellular binding mediated cell interactions and cell migration. Another SIRPalpha-specific residue, Met102, appears to assist SIRPalpha IgV binding through Gln67 and Ala/Val57. An essential role of these amino acid residues in SIRPalpha binding to CD47 was further confirmed by introducing these residues into the SIRPbeta1 IgV domain, which dramatically converts SIRPbeta1 into a CD47-binding molecule. Our results thus revealed the molecular basis by which SIRPalpha binds to CD47 and shed new light into the structural mechanisms of SIRP isoform mediated distinctive extracellular interactions and cellular responses.

Nrg4 promotes fuel oxidation and a healthy adipokine profile to ameliorate diet-induced metabolic disorders

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Zhimin Chen

2017-08-01

Conclusions: Nrg4 exerts pleiotropic beneficial effects on energy balance and glucose and lipid metabolism to ameliorate obesity-associated metabolic disorders. Biologic therapeutics based on Nrg4 may improve both type 2 diabetes and non-alcoholic fatty liver disease (NAFLD in patients.

The glycosylated IgII extracellular domain of EMMPRIN is implicated in the induction of MMP-2.

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Papadimitropoulou, Adriana; Mamalaki, Avgi

2013-07-01

EMMPRIN is a widely expressed transmembrane glycoprotein that plays important roles in many physiological and pathological processes, such as tumor invasion and metastasis. It stimulates the production of matrix metalloproteinase (MMPs) by tumor-associated fibroblasts. In the present study, our aim was to (a) to investigate if the IgII loop domain of the extracellular domain (ECD) of EMMPRIN contributes to the MMP production by fibroblasts and (b) to evaluate the significance of glycosylation in this process. For this purpose, we expressed the ECD, IgI, or IgII domains of EMMPRIN, in their glycosylated and non-glycosylated forms, in the heterologous expression systems of P. pastoris and E. coli, respectively. Dermal fibroblasts were treated with purified recombinant domains and proteins from cell extracts and supernatants were analyzed by Western blot and zymography assays. Fibroblasts treated with ECD-, IgI-, and IgII-glycosylated domains of EMMPRIN significantly stimulated the gelatinolytic activity of MMP-2, compared to untreated fibroblasts, whereas no significant effect was observed after treatment with the non-glycosylated ECD, IgI, and IgII domains. Western blot analysis from cell extracts and supernatants revealed that only the glycosylated forms were able to stimulate MMP-2 production and secretion, respectively. Quantitative PCR revealed that this effect was not attributed to transcriptional alterations. This study showed that N-glycosylation was a prerequisite for efficient MMP-2 production, with the IgII loop domain contributing significantly to this process. Perturbation of the function of IgII-EMMPRIN loop could have potential therapeutic value in the inhibition of MMP-2-dependent cancer cell invasion and metastasis.

Paradoxical effects of Auger electron-emitting 111In-DTPA-NLS-CSL360 radioimmunoconjugates on hCD45+ cells in the bone marrow and spleen of leukemia-engrafted NOD/SCID or NRG mice

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Bergstrom, Dane; Leyton, Jeffrey V.; Zereshkian, Arman; Chan, Conrad; Cai, Zhongli; Reilly, Raymond M.

2016-01-01

Introduction: 111 In-DTPA-NLS-CSL360 radioimmunoconjugates (RIC) recognize the overexpression of the interleukin-3 receptor α-subchain (CD123) relative to the β-subchain (CD131) on leukemia stem cells (LSC). Our aim was to study Auger electron radioimmunotherapy (RIT) of acute myeloid leukemia (AML) with 111 In-DTPA-NLS-CSL360 in non-obese diabetic severe combined immunodeficiency (NOD/SCID) mice or NOD-Rag1 null IL2rγ null (NRG) mice engrafted with CD123 + human AML-5 cells. Methods: The toxicity of three doses of 111 In-DTPA-NLS-CSL360 (3.3–4.8 MBq; 11–15 μg each) injected i.v. every two weeks was studied in non-engrafted NOD/SCID or NRG mice pre-treated with 200 cGy of γ-radiation required for AML engraftment. Engraftment efficiency of (1–5) × 10 6 cells AML-5 cells inoculated i.v. into NOD/SCID or NRG mice was assessed by flow cytometric analysis for human CD45 + (hCD45 + ) cells in the bone marrow (BM) and spleen. AML-5 engrafted mice were treated with two or three doses (3.7 MBq; 10 μg each) every two weeks of 111 In-DTPA-NLS-CSL360, non-specific 111 In-DTPA-NLS-hIgG, unlabeled CSL360 (10 μg) or normal saline. The percentage of hCD45 + cells in the BM and spleen were measured at one week after completion of treatment. Results: 111 In-DTPA-NLS-CSL360 in combination with 200 cGy of γ-radiation caused an initial transient decrease in body weight in NOD/SCID but not in NRG mice. There were no hematological, liver or kidney toxicities. The spleen exhibited 13-fold lower engraftment efficiency than the BM in NOD/SCID mice inoculated with 1 × 10 6 cells but both organs were highly (>85%) engrafted in NRG mice. Unexpectedly, 111 In-DTPA-NLS-CSL360 or non-specific 111 In-DTPA-NLS-hIgG caused a paradoxical 1.5-fold increase (P < 0.0001) in the proportion of hCD45 + cells in the BM of NOD/SCID mice compared to normal saline treated mice. 111 In-DTPA-NLS-CSL360 reduced hCD45 + cells in the spleen by 3.0-fold compared to 111 In-DTPA-NLS-hIgG (P = 0

Monoclonal antibodies for the identification and purification of vNAR domains and IgNAR immunoglobulins from the horn shark Heterodontus francisci.

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Juarez, Karla; Dubberke, Gudrun; Lugo, Pavel; Koch-Nolte, Friedrich; Buck, Friedrich; Haag, Friedrich; Licea, Alexei

2011-08-01

In addition to conventional antibodies, cartilaginous fish have evolved a distinctive type of immunoglobulin, designated as IgNAR, which lacks the light polypeptide chains and is composed entirely by heavy chains. IgNAR molecules can be manipulated by molecular engineering to produce the variable domain of a single heavy chain polypeptide (vNARs). These, together with the VHH camel domains, constitute the smallest naturally occurring domains able to recognize an antigen. Their special features, such as small size, long extended finger-like CDR3, and thermal and chemical stability, make them suitable candidates for biotechnological purposes. Here we describe the generation of two mouse monoclonal antibodies (MAbs), MAb 370-12 and MAb 533-10, that both specifically react with vNAR domains of the horn shark Heterodontus francisci. While the former recognizes a broad spectrum of recombinant vNAR proteins, the latter is more restricted. MAb 370-12 precipitated a single band from whole shark serum, which was identified as IgNAR by mass spectrometry. Additionally, we used MAb 370-12 to follow the IgNAR-mediated immune response of sharks during immunization protocols with two different antigens (complete cells and a synthethic peptide), thus corroborating that MAb 370-12 recognizes both isolated vNAR domains and whole IgNAR molecules. Both MAbs represent an affordable molecular, biochemical, and biotechnological tool in the field of shark single-domain antibodies.

Generation and characterization of ABT-981, a dual variable domain immunoglobulin (DVD-Ig(TM)) molecule that specifically and potently neutralizes both IL-1α and IL-1β.

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Lacy, Susan E; Wu, Chengbin; Ambrosi, Dominic J; Hsieh, Chung-Ming; Bose, Sahana; Miller, Renee; Conlon, Donna M; Tarcsa, Edit; Chari, Ravi; Ghayur, Tariq; Kamath, Rajesh V

2015-01-01

Interleukin-1 (IL-1) cytokines such as IL-1α, IL-1β, and IL-1Ra contribute to immune regulation and inflammatory processes by exerting a wide range of cellular responses, including expression of cytokines and chemokines, matrix metalloproteinases, and nitric oxide synthetase. IL-1α and IL-1β bind to IL-1R1 complexed to the IL-1 receptor accessory protein and induce similar physiological effects. Preclinical and clinical studies provide significant evidence for the role of IL-1 in the pathogenesis of osteoarthritis (OA), including cartilage degradation, bone sclerosis, and synovial proliferation. Here, we describe the generation and characterization of ABT-981, a dual variable domain immunoglobulin (DVD-Ig) of the IgG1/k subtype that specifically and potently neutralizes IL-1α and IL-1β. In ABT-981, the IL-1β variable domain resides in the outer domain of the DVD-Ig, whereas the IL-1α variable domain is located in the inner position. ABT-981 specifically binds to IL-1α and IL-1β, and is physically capable of binding 2 human IL-1α and 2 human IL-1β molecules simultaneously. Single-dose intravenous and subcutaneous pharmacokinetics studies indicate that ABT-981 has a half-life of 8.0 to 10.4 d in cynomolgus monkey and 10.0 to 20.3 d in rodents. ABT-981 exhibits suitable drug-like-properties including affinity, potency, specificity, half-life, and stability for evaluation in human clinical trials. ABT-981 offers an exciting new approach for the treatment of OA, potentially addressing both disease modification and symptom relief as a disease-modifying OA drug.

Aberrantly Glycosylated IgA1 as a Factor in the Pathogenesis of IgA Nephropathy

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Mototsugu Tanaka

2011-01-01

Full Text Available Predominant or codominant immunoglobulin (Ig A deposition in the glomerular mesangium characterizes IgA nephropathy (IgAN. Accumulated glomerular IgA is limited to the IgA1 subclass and usually galactose-deficient. This underglycosylated IgA may play an important role in the pathogenesis of IgAN. Recently, antibodies against galactose-deficient IgA1 were found to be well associated with the development of IgAN. Several therapeutic strategies based on corticosteroids or other immunosuppressive agents have been shown to at least partially suppress the progression of IgAN. On the other hand, several case reports of kidney transplantation or acquired IgA deficiency uncovered a remarkable ability of human kidney to remove mesangial IgA deposition, resulting in the long-term stabilization of kidney function. Continuous exposure to circulating immune complexes containing aberrantly glycosylated IgA1 and sequential immune response seems to be essential in the disease progression of IgAN. Removal of mesangial IgA deposition may be a challenging, but fundamental approach in the treatment of IgAN.

Tim-4 inhibition of T-cell activation and T helper type 17 differentiation requires both the immunoglobulin V and mucin domains and occurs via the mitogen-activated protein kinase pathway.

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Cao, Wei

2011-06-01

Emerging experimental data suggest an important role for the T-cell immunoglobulin mucin 1 (Tim-1):Tim-4 pathway in autoimmune and alloimmune responses in vivo. Using a Tim-4 ectodomain human IgG Fc fusion protein we studied the role of Tim-4 in T-cell activation, signalling and differentiation responses in vitro. We demonstrate that Tim-4Fc can inhibit naive and pre-activated T-cell activation, proliferation and cytokine secretion via a Tim-1-independent pathway. Tim-4 contains immunoglobulin variable (IgV) and mucin domains; to identify which domain accounts for the inhibitory effect novel Tim-4 fusion proteins containing either the IgV or mucin domain were generated. We demonstrate that both IgV and mucin domains are required for the inhibitory effects and that they are mediated at least in part by inhibition of extracellular signal-regulated kinase pathway activity. Given the emerging interest in the role of the Tim family in T helper type 17 (Th17) cells, which play an important role in autoimmune disease and transplantation tolerance, our data show that Tim-4Fc can prevent polarization of CD4(+) T cells to the Th17 phenotype. Collectively, our results highlight an inhibitory role for Tim-4Fc in vitro, which we propose is mediated by a receptor other than Tim-1. In addition, this study provides new insights into the role of Tim-4Fc in regulating Th17 immune responses and may open a new avenue for autoimmune therapy.

Tim-4 inhibition of T-cell activation and T helper type 17 differentiation requires both the immunoglobulin V and mucin domains and occurs via the mitogen-activated protein kinase pathway

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Cao, Wei; Ryan, Michelle; Buckley, Deirdre; O'Connor, Rosemary; Clarkson, Michael R

2011-01-01

Emerging experimental data suggest an important role for the T-cell immunoglobulin mucin 1 (Tim-1):Tim-4 pathway in autoimmune and alloimmune responses in vivo. Using a Tim-4 ectodomain human IgG Fc fusion protein we studied the role of Tim-4 in T-cell activation, signalling and differentiation responses in vitro. We demonstrate that Tim-4Fc can inhibit naive and pre-activated T-cell activation, proliferation and cytokine secretion via a Tim-1-independent pathway. Tim-4 contains immunoglobulin variable (IgV) and mucin domains; to identify which domain accounts for the inhibitory effect novel Tim-4 fusion proteins containing either the IgV or mucin domain were generated. We demonstrate that both IgV and mucin domains are required for the inhibitory effects and that they are mediated at least in part by inhibition of extracellular signal-regulated kinase pathway activity. Given the emerging interest in the role of the Tim family in T helper type 17 (Th17) cells, which play an important role in autoimmune disease and transplantation tolerance, our data show that Tim-4Fc can prevent polarization of CD4+ T cells to the Th17 phenotype. Collectively, our results highlight an inhibitory role for Tim-4Fc in vitro, which we propose is mediated by a receptor other than Tim-1. In addition, this study provides new insights into the role of Tim-4Fc in regulating Th17 immune responses and may open a new avenue for autoimmune therapy. PMID:21463297

Detection of IgG1 and IgG4 subtypes reactive against potato apyrase in schistosomiasis patients

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Priscila de Faria-Pinto

2010-07-01

Full Text Available In this paper, we showed for the first time that the conserved domains within Schistosoma mansoni ATP diphosphohydrolase isoforms, shared with potato apyrase, possess epitopes for the IgG1 and IgG4 subtypes, as 24 (80% of the 30 schistosomiasis patients were seropositive for this vegetable protein. The analyses for each patient cured (n = 14 after treatment (AT with praziquantel revealed variable IgG1 and IgG4 reactivity against potato apyrase. Different antigenic epitopes shared between the vegetable and parasite proteins could be involved in susceptibility or resistance to S. mansoni AT with praziquantel and these possibilities should be explored.

Structure of the EMMPRIN N-terminal domain 1: Dimerization via [beta]-strand swapping

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Luo, Jinquan; Teplyakov, Alexey; Obmolova, Galina; Malia, Thomas; Wu, Sheng-Jiun; Beil, Eric; Baker, Audrey; Swencki-Underwood, Bethany; Zhao, Yonghong; Sprenkle, Justin; Dixon, Ken; Sweet, Raymond; Gilliland, Gary L.; (Centocor)

2010-09-27

Extracellular matrix metalloproteinase inducer (EMMPRIN), also known as Hab18G, CD147, Basigin, M6, and neurothelin, is a membrane glycoprotein expressed on the surface of various cell types and many cancer cells. EMMPRIN stimulates adjacent fibroblasts and tumor cells to produce matrix metalloproteinases and plays an important role in tumor invasion and metastasis, angiogenesis, spermatogensis and fertilization, cell-cell adhesion and communication, and other biological processes (reviewed in Ref. 1 and references therein). It was demonstrated that the EMMPRIN extracellular domain (ECD), which structurally belongs to the IgG superfamily, can form homo-oligomers in a cis dependent manner and the N-terminal domain 1 (residues 22-101) was necessary and sufficient to mediate this interaction. The crystal structure of the ECD of recombinant human EMMPRIN (Hab18G/CD147) expressed in E. coli was reported at 2.8 {angstrom} resolution (Yu et al. 2008). The construct consists of residues 22-205 of the mature protein and has both an N-terminal IgC2 domain (ND1, residues 22-101) and a C-terminal IgC2 domain (ND2, residues 107-205). The two domains are joined by a five amino acid residue linker that constitutes a flexible hinge between the two domains. The crystal form has four copies of the molecule in the asymmetric unit, each of which has a different inter-domain angle that varies from 121{sup o} to 144{sup o}. The two domains each have a conserved disulfide bridge and both are comprised of two {beta}-sheets formed by strands EBA and GFCC, and DEBA and AGFCC for ND1 and ND2, respectively. Based on the crystal packing in this structure, the authors proposed that lateral packing between the two IgG domains of EMMPRIN ECD represents a potential mechanism for cell adhesion. Here we report the 2.0-{angstrom} crystal structure of the N-terminal domain of EMMPRIN ECD (ND1) expressed in mammalian cells. The overall structure of the domain is very similar to that in the full length

Extensive diversification of IgD-, IgY-, and truncated IgY(δFc)-encoding genes in the red-eared turtle (Trachemys scripta elegans).

Science.gov (United States)

Li, Lingxiao; Wang, Tao; Sun, Yi; Cheng, Gang; Yang, Hui; Wei, Zhiguo; Wang, Ping; Hu, Xiaoxiang; Ren, Liming; Meng, Qingyong; Zhang, Ran; Guo, Ying; Hammarström, Lennart; Li, Ning; Zhao, Yaofeng

2012-10-15

IgY(ΔFc), containing only CH1 and CH2 domains, is expressed in the serum of some birds and reptiles, such as ducks and turtles. The duck IgY(ΔFc) is produced by the same υ gene that expresses the intact IgY form (CH1-4) using different transcriptional termination sites. In this study, we show that intact IgY and IgY(ΔFc) are encoded by distinct genes in the red-eared turtle (Trachemys scripta elegans). At least eight IgY and five IgY(ΔFc) transcripts were found in a single turtle. Together with Southern blotting, our data suggest that multiple genes encoding both IgY forms are present in the turtle genome. Both of the IgY forms were detected in the serum using rabbit polyclonal Abs. In addition, we show that multiple copies of the turtle δ gene are present in the genome and that alternative splicing is extensively involved in the generation of both the secretory and membrane-bound forms of the IgD H chain transcripts. Although a single μ gene was identified, the α gene was not identified in this species.

Primary breast cancer tumours contain high amounts of IgA1 immunoglobulin

DEFF Research Database (Denmark)

Welinder, Charlotte; Baldetorp, Bo; Blixt, Klas Ola

2013-01-01

seen in the percentage of stained cells and in the staining pattern in the different breast cancers analysed. Anti-Tn antibody and HPA were also shown to specifically bind to a number of possible constellations of the Tn antigen in the hinge region of IgA1. Both reagents could also detect the presence....... The short O-glycan that forms the antigen is carried by a number of different proteins. One potential carrier of the Tn antigen is immunoglobulin A1 (IgA1), which we surprisingly found in tumour cells of the invasive parts of primary breast carcinoma. Conventional immunohistochemical analysis of paraffin......-embedded sections from primary breast cancers showed IgA1 to be present in the cytoplasm and plasma membrane of 35 out of 36 individual primary tumours. The immunohistochemical staining of HPA and anti-Tn antibody (GOD3-2C4) did to some extent overlap with the presence of IgA1 in the tumours, but differences were...

Genetic association between NRG1 and schizophrenia, major depressive disorder, bipolar disorder in Han Chinese population.

Science.gov (United States)

Wen, Zujia; Chen, Jianhua; Khan, Raja Amjad Waheed; Song, Zhijian; Wang, Meng; Li, Zhiqiang; Shen, Jiawei; Li, Wenjin; Shi, Yongyong

2016-04-01

Schizophrenia, major depressive disorder, and bipolar disorder are three major psychiatric disorders affecting around 0.66%, 3.3%, and 1.5% of the Han Chinese population respectively. Several genetic linkage analyses and genome wide association studies identified NRG1 as a susceptibility gene of schizophrenia, which was validated by its role in neurodevelopment, glutamate, and other neurotransmitter receptor expression regulation. To further investigate whether NRG1 is a shared risk gene for major depressive disorder, bipolar disorder as well as schizophrenia, we performed an association study among 1,248 schizophrenia cases, 1,056 major depression cases, 1,344 bipolar disorder cases, and 1,248 controls. Totally 15 tag SNPs were genotyped and analyzed, and no population stratification was found in our sample set. Among the sites, rs4236710 (corrected Pgenotye  = 0.015) and rs4512342 (Pallele  = 0.03, Pgenotye  = 0.045 after correction) were associated with schizophrenia, and rs2919375 (corrected Pgenotye  = 0.004) was associated with major depressive disorder. The haplotype rs4512342-rs6982890 showed association with schizophrenia (P = 0.03 for haplotype "TC" after correction), and haplotype rs4531002-rs11989919 proved to be a shared risk factor for both major depressive disorder ("CC": corrected P = 0.009) and bipolar disorder ("CT": corrected P = 0.003). Our results confirmed that NRG1 was a shared common susceptibility gene for major mental disorders in Han Chinese population. © 2016 Wiley Periodicals, Inc.

Amino acid sequence requirements in the hinge of human immunoglobulin A1 (IgA1) for cleavage by streptococcal IgA1 proteases

DEFF Research Database (Denmark)

Batten, MR; Senior, BW; Kilian, Mogens

2003-01-01

The amino acid sequence requirements in the hinge of human immunoglobulin A1 (IgA1) for cleavage by IgA1 proteases of different species of Streptococcus were investigated. Recombinant IgA1 antibodies were generated with point mutations at proline 227 and threonine 228, the residues lying on either...... side of the peptide bond at which all streptococcal IgA1 proteases cleave wild-type human IgA1. The amino acid substitutions produced no major effect upon the structure of the mutant IgA1 antibodies or their functional ability to bind to Fcalpha receptors. However, the substitutions had a substantial...... effect upon sensitivity to cleavage with some streptococcal IgA1 proteases, with, in some cases, a single point mutation rendering the antibody resistant to a particular IgA1 protease. This effect was least marked with the IgA1 protease from Streptococcus pneumoniae, which showed no absolute requirement...

Identification of high-mannose and multiantennary complex-type N-linked glycans containing alpha-galactose epitopes from Nurse shark IgM heavy chain.

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Harvey, David J; Crispin, Max; Moffatt, Beryl E; Smith, Sylvia L; Sim, Robert B; Rudd, Pauline M; Dwek, Raymond A

2009-11-01

MALDI-TOF mass spectrometry, negative ion nano-electrospray MS/MS and exoglycosidase digestion were used to identify 36 N-linked glycans from 19S IgM heavy chain derived from the nurse shark (Ginglymostoma cirratum). The major glycan was the high-mannose compound, Man(6)GlcNAc(2) accompanied by small amounts of Man(5)GlcNAc(2), Man(7)GlcNAc(2) and Man(8)GlcNAc(2). Bi- and tri-antennary (isomer with a branched 3-antenna) complex-type glycans were also abundant, most contained a bisecting GlcNAc residue (beta1-->4-linked to the central mannose) and with varying numbers of alpha-galactose residues capping the antennae. Small amounts of monosialylated glycans were also found. This appears to be the first comprehensive study of glycosylation in this species of animal. The glycosylation pattern has implications for the mechanism of activation of the complement system by nurse shark IgM.

Discovery, validation and characterization of Erbb4 and Nrg1 haplotypes using data from three genome-wide association studies of schizophrenia.

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Zeynep Sena Agim

Full Text Available Schizophrenia is one of the most common and complex neuropsychiatric disorders, which is contributed both by genetic and environmental exposures. Recently, it is shown that NRG1-mediated ErbB4 signalling regulates many important cellular and molecular processes such as cellular growth, differentiation and death, particularly in myelin-producing cells, glia and neurons. Recent association studies have revealed genomic regions of NRG1 and ERBB4, which are significantly associated with risk of developing schizophrenia; however, inconsistencies exist in terms of validation of findings between distinct populations. In this study, we aim to validate the previously identified regions and to discover novel haplotypes of NRG1 and ERBB4 using logistic regression models and Haploview analyses in three independent datasets from GWAS conducted on European subjects, namely, CATIE, GAIN and nonGAIN. We identified a significant 6-kb block in ERBB4 between chromosome locations 212,156,823 and 212,162,848 in CATIE and GAIN datasets (p = 0.0206 and 0.0095, respectively. In NRG1, a significant 25-kb block, between 32,291,552 and 32,317,192, was associated with risk of schizophrenia in all CATIE, GAIN, and nonGAIN datasets (p = 0.0005, 0.0589, and 0.0143, respectively. Fine mapping and FastSNP analysis of genetic variation located within significantly associated regions proved the presence of binding sites for several transcription factors such as SRY, SOX5, CEPB, and ETS1. In this study, we have discovered and validated haplotypes of ERBB4 and NRG1 in three independent European populations. These findings suggest that these haplotypes play an important role in the development of schizophrenia by affecting transcription factor binding affinity.

Antiapolipoprotein A-1 IgG chronotropic effects require nongenomic action of aldosterone on L-type calcium channels.

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Rossier, Michel F; Pagano, Sabrina; Python, Magaly; Maturana, Andres D; James, Richard W; Mach, François; Roux-Lombard, Pascale; Vuilleumier, Nicolas

2012-03-01

Autoantibodies to apolipoprotein A-1 (antiapoA-1 IgG) have been shown to be associated with higher resting heart rate and morbidity in myocardial infarction patients and to behave as a chronotropic agent in the presence of aldosterone on isolated neonatal rat ventricular cardiomyocytes (NRVC). We aimed at identifying the pathways accounting for this aldosterone-dependent antiapoA-1 IgG-positive chronotropic effect on NRVC. The rate of regular spontaneous contractions was determined on NRVC in the presence of different steroid hormones and antagonists. AntiapoA-1 IgG chronotropic response was maximal within 20 min and observed only in aldosterone-pretreated cells but not in those exposed to other steroids. The positive antiapoA-1 IgG chronotropic effect was already significant after 5 min aldosterone preincubation, was dependent on 3-kinase and protein kinase A activities, was not inhibited by actinomycin D, and was fully abrogated by eplerenone (but not by spironolactone), demonstrating the dependence on a nongenomic action of aldosterone elicited through the mineralocorticoid receptor (MR). Under oxidative conditions (but not under normal redox state), corticosterone mimicked the permissive action of aldosterone on the antiapoA-1 IgG chronotropic response. Pharmacological and patch-clamp studies identified L-type calcium channels as crucial effectors of antiapoA-1 IgG chronotropic action, involving two converging pathways that increase the channel activity. The first one involves the rapid, nongenomic activation of the phosphatidylinositol 3-kinase enzyme by MR, and the second one requires a constitutive basal protein kinase A activity. In conclusion, our results indicate that, on NRVC, the aldosterone-dependent chronotropic effects of antiapoA-1 IgG involve the nongenomic activation of L-type calcium channels.

Purification, crystallization and preliminary X-ray analysis of the IgV domain of human nectin-4

International Nuclear Information System (INIS)

Xu, Xiang; Zhang, Xiaoai; Lu, Guangwen; Cai, Yongping

2012-01-01

Nectin-4 belongs to a family of immunoglobulin-like cell adhesion molecules and is highly expressed in cancer cells. Recently, nectin-4 was found to be a receptor of measles virus and the IgV domain sustains strong binding to measles virus H protein. In this study, the successful expression and purification of human nectin-4 V domain (nectin-4v) is reported Nectin-4 belongs to a family of immunoglobulin-like cell adhesion molecules and is highly expressed in cancer cells. Recently, nectin-4 was found to be a receptor of measles virus and the IgV domain sustains strong binding to measles virus H protein. In this study, the successful expression and purification of human nectin-4 V domain (nectin-4v) is reported. The purified protein was crystallized using the sitting-drop vapour-diffusion method. The crystals diffracted to 1.8 Å resolution and belonged to space group P2 1 , with unit-cell parameters a = 33.1, b = 51.7, c = 56.9 Å, β = 94.7°. Preliminary analysis of the diffraction data was also performed

Neuregulin 1: a prime candidate for research into gene-environment interactions in schizophrenia? Insights from genetic rodent models

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Tim eKarl

2013-08-01

Full Text Available Schizophrenia is a multi-factorial disease characterized by a high heritability and environmental risk factors. In recent years, an increasing number of researchers worldwide have started investigating the ‘two-hit hypothesis’ of schizophrenia predicting that genetic and environmental risk factors (GxE interactively cause the development of the disorder. This work is starting to produce valuable new animal models and reveal novel insights into the pathophysiology of schizophrenia. This mini review will focus on recent advancements in the field made by challenging mutant and transgenic rodent models for the schizophrenia candidate gene neuregulin 1 (NRG1 with particular environmental factors. It will outline results obtained from mouse and rat models for various Nrg1 isoforms/isoform types (e.g. transmembrane domain Nrg1, Type II Nrg1, which have been exposed to different forms of stress (acute versus chronic, restraint versus social and housing conditions (standard laboratory versus minimally enriched housing. These studies suggest Nrg1 as a prime candidate for GxE interactions in schizophrenia rodent models and that the use of rodent models will enable a better understanding of GxE interactions and the underlying mechanisms.

Radioimmunoassay for detection of IgM domains

Energy Technology Data Exchange (ETDEWEB)

Shimizu, A [Osaka Univ. (Japan); Watanabe, S; Kiyotaki, C; Yamamura, Y

1979-09-01

IgM from two macroglobulinemia patients was digested with trypsin, and Fab monomer, Fab dimer and Fc fragments of the IgM were isolated. Using these fragments as antigens and rabbit antisera prepared against another IgM from a macroglobulinemia patient, a radioimmunoassay system for the C..mu..1, C..mu..2 and Fc..mu.. was established. This system can be used as a tool for immunochemical characterization of IgM present on the surface of lymphoid cells.

Transient glyco-engineering to produce recombinant IgA1 with defined N- and O-glycans in plants

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Martina eDicker

2016-01-01

Full Text Available The production of therapeutic antibodies to combat pathogens and treat diseases such as cancer is of great interest for the biotechnology industry. The recent development of plant-based expression systems has demonstrated that plants are well-suited for the production of recombinant monoclonal antibodies with defined glycosylation. Compared to immunoglobulin G (IgG, less effort has been undertaken to express immunoglobulin A (IgA, which is the most prevalent antibody class at mucosal sites and a promising candidate for novel recombinant biopharmaceuticals with enhanced anti-tumour activity. Here, we transiently expressed recombinant human IgA1 against the VP8* rotavirus antigen in glyco-engineered deltaXT/FT Nicotiana benthamiana plants. Mass spectrometric analysis of IgA1 glycopeptides revealed the presence of complex biantennary N-glycans with terminal N-acetylglucosamine present on the N-glycosylation site of the CH2 domain in the IgA1 alpha chain. Analysis of the peptide carrying nine potential O-glycosylation sites in the IgA1 alpha chain hinge region showed the presence of plant-specific modifications including hydroxyproline formation and the attachment of pentoses. By co-expression of enzymes required for initiation and elongation of human O-glycosylation it was possible to generate disialylated mucin-type core 1 O-glycans on plant-produced IgA1. Our data demonstrate that deltaXT/FT Nicotiana benthamiana plants can be engineered towards the production of recombinant IgA1 with defined human-type N- and O-linked glycans.

eCD4-Ig variants that more potently neutralize HIV-1.

Science.gov (United States)

Fetzer, Ina; Gardner, Matthew R; Davis-Gardner, Meredith E; Prasad, Neha R; Alfant, Barnett; Weber, Jesse A; Farzan, Michael

2018-03-28

The HIV-1 entry inhibitor eCD4-Ig is a fusion of CD4-Ig and a coreceptor-mimetic peptide. eCD4-Ig is markedly more potent than CD4-Ig, with neutralization efficiencies approaching those of HIV-1 broadly neutralizing antibodies (bNAbs). However, unlike bNAbs, eCD4-Ig neutralizes all HIV-1, HIV-2 and SIV isolates that it has been tested against, suggesting that it may be useful in clinical settings where antibody escape is a concern. Here we characterize three new eCD4-Ig variants, each with different architectures and each utilizing D1.22, a stabilized form of CD4 domain 1. These variants were 10- to 20-fold more potent than our original eCD4-Ig variant, with a construct bearing four D1.22 domains (eD1.22-HL-Ig) exhibiting the greatest potency. However, this variant mediated less efficient antibody-dependent cell-mediated cytotoxicity (ADCC) activity than eCD4-Ig itself or several other eCD4-Ig variants, including the smallest variant (eD1.22-Ig). A variant with the same architecture as original eCD4-Ig (eD1.22-D2-Ig) showed modestly higher thermal stability and best prevented promotion of infection of CCR5-positive, CD4-negative cells. All three variants, and eCD4-Ig itself, mediated more efficient shedding of the HIV-1 envelope glycoprotein gp120 than did CD4-Ig. Finally, we show that only three D1.22 mutations contributed to the potency of eD1.22-D2-Ig, and that introduction of these changes into eCD4-Ig resulted in a variant 9-fold more potent than eCD4-Ig and 2-fold more potent than eD1.22-D2-Ig. These studies will assist in developing eCD4-Ig variants with properties optimized for prophylaxis, therapy, and cure applications. IMPORTANCE HIV-1 bNAbs have properties different from antiretroviral compounds. Specifically, antibodies can enlist immune effector cells to eliminate infected cells, whereas antiretroviral compounds simply interfere with various steps in the viral lifecycle. Unfortunately, HIV-1 is adept at evading antibody recognition, limiting the

[A case of IgA2-lambda type M-protein that IgA concentration differs from the values of M-protein by serum protein electrophoresis].

Science.gov (United States)

Fukushima, M; Sugano, M; Ichikawa, T; Honda, T; Totsuka, M; Katsuyama, T; Fujita, K

2001-07-01

We report an IgA-lambda type M-protein in which the IgA concentration differed from the values of M-protein by serum protein electrophoresis found in a 53-year-old man with multiple myeloma. The M-protein value as determined by serum protein electrophoresis was 6,170 mg/dl. However, the serum IgA concentration was 3,052 mg/dl by turbidimetric immunoassay. Immuno-fixation electrophoresis using IgA subclass antisera revealed that this M-protein was the IgA2-lambda type. Western blotting analysis showed that the IgA2 molecules were composed of two approximately 68 kDa alpha 2 chains and two 28 kDa lambda chains. In addition the free lambda chain band was detected at the position of 28 kDa without 2-mercaptoethanol(2-ME) even though the patient IgA was purified. Since it is known that IgA2m(1) allotype easily release light chains from the IgA molecules in SDS-PAGE without 2-ME, we speculated that in this patient the IgA was the IgA2m(1) allotype. After peripheral blood stem cell transplantation(PBSCT), immunofixation electrophoresis of the patient serum revealed not only the bands of IgA2-lambda type M-protein, but also three bands of IgG1-kappa type M-protein in the gamma region.

In search of periodic signatures in IGS REPRO1 solution

Science.gov (United States)

Mtamakaya, J. D.; Santos, M. C.; Craymer, M. R.

2010-12-01

We have been looking for periodic signatures in the REPRO1 solution recently released by the IGS. At this stage, a selected sub-set of IGS station time series in position and residual domain are under harmonic analysis. We can learn different things from this analysis. From the position domain, we can learn more about actual station motions. From the residual domain, we can learn more about mis-modelled or un-modelled errors. As far as error sources are concerned, we have investigated effects that may be due to tides, atmospheric loading, definition of the position of the figure axis and GPS constellation geometry. This poster presents and discusses our findings and presents insights on errors that need to be modelled or have their models improved.

Parvalbumin, a cross-reactive fish allergen, contains IgE-binding epitopes sensitive to periodate treatment and Ca2+ depletion.

Science.gov (United States)

Bugajska-Schretter, A; Elfman, L; Fuchs, T; Kapiotis, S; Rumpold, H; Valenta, R; Spitzauer, S

1998-01-01

Type I allergy to fish is a severe health problem in countries in which a large percentage of the population derive income from fishing. The aim of the study was to characterize cross-reactive IgE-binding components in six different fish species (cod, tuna, salmon, perch, carp, and eel). The effect of reducing extraction conditions, periodate treatment, and depletion of Ca2+ on binding of IgE to the allergens was investigated. Extracts were prepared under nonreducing and reducing conditions. IgE-binding components were characterized by IgE immunoblotting, and cross-reactive epitopes were studied by IgE-immunoblot inhibition experiments. To reveal calcium-sensitive or carbohydrate-containing epitopes, nitrocellulose-blotted extracts were exposed to ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) and periodate. Sera from all patients allergic to fish (n = 30) displayed IgE reactivity to parvalbumin, a 12 kd protein present in fish extracts from six different species. Reducing extraction conditions had no effect on IgE binding to parvalbumins, whereas periodate treatment and depletion of protein-bound calcium led to a substantial reduction of IgE binding. Parvalbumins from six different species contained cross-reactive IgE epitopes. Parvalbumin represents a cross-reactive fish allergen. It contains IgE epitopes that are sensitive to periodate treatment and Ca2+-depletion.

Multiple Plasmodium falciparum erythrocyte membrane protein 1 variants per genome can bind IgM via its Fc fragment Fcμ

DEFF Research Database (Denmark)

Jeppesen, Anine; Ditlev, Sisse Bolm; Soroka, Vladyslav

2015-01-01

with severe clinical manifestations, such as cerebral malaria in children and placental malaria in pregnant women. PfEMP1 that can bind the Fc part of IgM (Fcμ) characterizes one such type, although the functional significance of this IgM binding to PfEMP1 remains unclear. In this study, we report...... resemble the rosette-mediating and IgM-binding PfEMP1 HB3VAR06, but none of them mediated formation of rosettes. We could map the capacity for Fc-specific IgM binding to DBLε domains near the C terminus for three of the four PfEMP1 proteins tested. Our study provides new evidence regarding Fc...

A recombinant hypoallergenic parvalbumin mutant for immunotherapy of IgE-mediated fish allergy.

Science.gov (United States)

Swoboda, Ines; Bugajska-Schretter, Agnes; Linhart, Birgit; Verdino, Petra; Keller, Walter; Schulmeister, Ulrike; Sperr, Wolfgang R; Valent, Peter; Peltre, Gabriel; Quirce, Santiago; Douladiris, Nikolaos; Papadopoulos, Nikolaos G; Valenta, Rudolf; Spitzauer, Susanne

2007-05-15

IgE-mediated allergy to fish is a frequent cause of severe anaphylactic reactions. Parvalbumin, a small calcium-binding protein, is the major fish allergen. We have recently isolated a cDNA coding for carp parvalbumin, Cyp c 1, and expressed in Escherichia coli a recombinant Cyp c 1 molecule, which contained most IgE epitopes of saltwater and freshwater fish. In this study, we introduced mutations into the calcium-binding domains of carp parvalbumin by site-directed mutagenesis and produced in E. coli three parvalbumin mutants containing amino acid exchanges either in one (single mutants; Mut-CD and Mut-EF) or in both of the calcium-binding sites (double mutant; Mut-CD/EF). Circular dichroism analyses of the purified derivatives and the wild-type allergen showed that Mut-CD/EF exhibited the greatest reduction of overall protein fold. Dot blot assays and immunoblot inhibition experiments performed with sera from 21 fish-allergic patients showed that Mut-CD/EF had a 95% reduced IgE reactivity and represented the derivative with the least allergenic activity. The latter was confirmed by in vitro basophil histamine release assays and in vivo skin prick testing. The potential applicability for immunotherapy of Mut-CD/EF was demonstrated by the fact that mouse IgG Abs could be raised by immunization with the mutated molecule, which cross-reacted with parvalbumins from various fish species and inhibited the binding of fish-allergic patients' IgE to the wild-type allergen. Using the hypoallergenic carp parvalbumin mutant Mut-CD/EF, it may be possible to treat fish allergy by immunotherapy.

Immunoglobulins in nasal secretions of healthy humans: structural integrity of secretory immunoglobulin A1 (IgA1) and occurrence of neutralizing antibodies to IgA1 proteases of nasal bacteria

DEFF Research Database (Denmark)

Kirkeby, L; Rasmussen, TT; Reinholdt, Jesper

2000-01-01

Certain bacteria, including overt pathogens as well as commensals, produce immunoglobulin A1 (IgA1) proteases. By cleaving IgA1, including secretory IgA1, in the hinge region, these enzymes may interfere with the barrier functions of mucosal IgA antibodies, as indicated by experiments in vitro....... Previous studies have suggested that cleavage of IgA1 in nasal secretions may be associated with the development and perpetuation of atopic disease. To clarify the potential effect of IgA1 protease-producing bacteria in the nasal cavity, we have analyzed immunoglobulin isotypes in nasal secretions of 11...... healthy humans, with a focus on IgA, and at the same time have characterized and quantified IgA1 protease-producing bacteria in the nasal flora of the subjects. Samples in the form of nasal wash were collected by using a washing liquid that contained lithium as an internal reference. Dilution factors and...

[Analysis of Relationship between Serum Total Light Chain κ/λ Ratio and Proportion of Bone Marrow Plasma Cells in Patients with IgG type and IgA type Multiple Myeloma].

Science.gov (United States)

Zhu, An-You; Zhu, Fang-Bing; Wang, Feng-Chao; Zhang, Lun-Jun; Ma, Yue; Hu, Jian-Guo

2017-10-01

To explore the relationship between serum total light chain κ/λ ratio (sTLC-κ/λ) and proportion of bone marrow plasma cells (BMPC) in patients with IgG type and IgA type multiple myeloma (MM) and its clinical significance. The levels of serum IgG, IgA, κ type and λ type total light chain were detected in 79 newly diagnosed patients with IgG type (n=52) and IgA type (n=27) MM by immuno-nephelometric assay and the sTLC-κ/λ ratio was calculated. The proportion of BMPC was determined by bone marrow smears in the corresponding period, and the changes in sTLC-κ/λ ratio and the proportion of BMPC were observed in 19 patients with IgG type(n=16) and IgA type (n=3) MM undergoing treatment, 26 cases of non-phasmocytic proliferative diseases were enrolled in control group. In MM patients with IgGκ type and IgAκ type, the sTLC-κ/λ ratio was significantly higher than that in the control group (Pratio was significantly lower than that in the control group (Pratio was significantly higher than that in MM patients with IgAκ(Pratio in MM patients with IgGλ was significantly lower than that in MM patients with IgAλ. The sTLC-κ/λ ratios in MM patients with IgGκ and IgAκ were positively correlated with the concentrations of IgG (r=0.778,P=0.000) and IgA (r=0.601,P=0.039), while the sTLC-κ/λ ratios of patients with IgGλ and IgAλ were negativily correlated with the IgG(r=-0.586,P=0.01) and IgA level(r=-0.718,P=0.003). In addition, a correlation between each type MM was not found except the IgGκ type MM which had a positive correlation between the sTLC-κ/λ ratio and proportion of BMPC (r=0.579,P=0.002). Nonetheless, 18 of 19 patients with IgG type and IgA type MM undergoing treatment showed concordance between the sTLC-κ/λ ratio and proportion of BMPC change. There is a lower correlation between the sTLC-κ/λ ratio and the proportion of BMPC in MM patients with IgG type and IgA type, but there is a high concordance between the sTLC-κ/λ ratio and the

The Emerging Importance of IgG Fab Glycosylation in Immunity.

Science.gov (United States)

van de Bovenkamp, Fleur S; Hafkenscheid, Lise; Rispens, Theo; Rombouts, Yoann

2016-02-15

Human IgG is the most abundant glycoprotein in serum and is crucial for protective immunity. In addition to conserved IgG Fc glycans, ∼15-25% of serum IgG contains glycans within the variable domains. These so-called "Fab glycans" are primarily highly processed complex-type biantennary N-glycans linked to N-glycosylation sites that emerge during somatic hypermutation. Specific patterns of Fab glycosylation are concurrent with physiological and pathological conditions, such as pregnancy and rheumatoid arthritis. With respect to function, Fab glycosylation can significantly affect stability, half-life, and binding characteristics of Abs and BCRs. Moreover, Fab glycans are associated with the anti-inflammatory activity of IVIgs. Consequently, IgG Fab glycosylation appears to be an important, yet poorly understood, process that modulates immunity. Copyright © 2016 by The American Association of Immunologists, Inc.

Functional Elements on SIRPα IgV domain Mediate Cell Surface Binding to CD47

OpenAIRE

Liu, Yuan; Tong, Qiao; Zhou, Yubin; Lee, Hsiau-Wei; Yang, Jenny J.; Bühring, Hans-Jörg; Chen, Yi-Tien; Ha, Binh; Chen, Celia X-J.; Zen, Ke

2006-01-01

SIRPα and SIRPβ1, the two major isoforms of the signal regulatory protein (SIRP) family, are co-expressed in human leukocytes but mediate distinct extracellular binding interactions and divergent cell signaling responses. Previous studies have demonstrated that binding of SIRPα with CD47, another important cell surface molecule, through the extracellular IgV domain regulates important leukocyte functions including macrophage recognition, leukocyte adhesion and transmigration. Although SIRPβ1 ...

Dysregulated Expression of Neuregulin-1 by Cortical Pyramidal Neurons Disrupts Synaptic Plasticity

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Amit Agarwal

2014-08-01

Full Text Available Neuregulin-1 (NRG1 gene variants are associated with increased genetic risk for schizophrenia. It is unclear whether risk haplotypes cause elevated or decreased expression of NRG1 in the brains of schizophrenia patients, given that both findings have been reported from autopsy studies. To study NRG1 functions in vivo, we generated mouse mutants with reduced and elevated NRG1 levels and analyzed the impact on cortical functions. Loss of NRG1 from cortical projection neurons resulted in increased inhibitory neurotransmission, reduced synaptic plasticity, and hypoactivity. Neuronal overexpression of cysteine-rich domain (CRD-NRG1, the major brain isoform, caused unbalanced excitatory-inhibitory neurotransmission, reduced synaptic plasticity, abnormal spine growth, altered steady-state levels of synaptic plasticity-related proteins, and impaired sensorimotor gating. We conclude that an “optimal” level of NRG1 signaling balances excitatory and inhibitory neurotransmission in the cortex. Our data provide a potential pathomechanism for impaired synaptic plasticity and suggest that human NRG1 risk haplotypes exert a gain-of-function effect.

Dysregulated expression of neuregulin-1 by cortical pyramidal neurons disrupts synaptic plasticity.

Science.gov (United States)

Agarwal, Amit; Zhang, Mingyue; Trembak-Duff, Irina; Unterbarnscheidt, Tilmann; Radyushkin, Konstantin; Dibaj, Payam; Martins de Souza, Daniel; Boretius, Susann; Brzózka, Magdalena M; Steffens, Heinz; Berning, Sebastian; Teng, Zenghui; Gummert, Maike N; Tantra, Martesa; Guest, Peter C; Willig, Katrin I; Frahm, Jens; Hell, Stefan W; Bahn, Sabine; Rossner, Moritz J; Nave, Klaus-Armin; Ehrenreich, Hannelore; Zhang, Weiqi; Schwab, Markus H

2014-08-21

Neuregulin-1 (NRG1) gene variants are associated with increased genetic risk for schizophrenia. It is unclear whether risk haplotypes cause elevated or decreased expression of NRG1 in the brains of schizophrenia patients, given that both findings have been reported from autopsy studies. To study NRG1 functions in vivo, we generated mouse mutants with reduced and elevated NRG1 levels and analyzed the impact on cortical functions. Loss of NRG1 from cortical projection neurons resulted in increased inhibitory neurotransmission, reduced synaptic plasticity, and hypoactivity. Neuronal overexpression of cysteine-rich domain (CRD)-NRG1, the major brain isoform, caused unbalanced excitatory-inhibitory neurotransmission, reduced synaptic plasticity, abnormal spine growth, altered steady-state levels of synaptic plasticity-related proteins, and impaired sensorimotor gating. We conclude that an "optimal" level of NRG1 signaling balances excitatory and inhibitory neurotransmission in the cortex. Our data provide a potential pathomechanism for impaired synaptic plasticity and suggest that human NRG1 risk haplotypes exert a gain-of-function effect. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Anti-tumor immunotherapy by blockade of the PD-1/PD-L1 pathway with recombinant human PD-1-IgV.

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Zhang, C; Wu, S; Xue, X; Li, M; Qin, X; Li, W; Han, W; Zhang, Y

2008-01-01

Blockade of the programmed death-1 (PD-1)/PD-ligand 1 (PD-L1) pathway can delay tumor growth and prolong the survival of tumor-bearing mice. The extracellular immunoglobulin (Ig) V domain of PD-1 is important for the interaction between PD-1 and PD-L1, suggesting that PD-1-IgV may be a potential target for anti-tumor immunotherapy. The extracellular sequence of human PD-1-IgV (hPD-1-IgV) was expressed in Escherichia coli and purified. The anti-tumor effect of hPD-1-IgV on tumor-bearing mice was tested. hPD-1-IgV recombinant protein could bind PD-L1 at molecular and cellular levels and enhance Cytotoxic T Lymphocyte (CTL) activity and anti-tumor effect on tumor-bearing mice in vivo. The percentage of CD4(+)CD25(+) T cells in tumor-bearing mice was decreased compared with control mice after administration of the recombinant protein. Our results suggest that inhibition of the interaction between PD-1 and PD-L1 by hPD-1-IgV may be a promising strategy for specific tumor immunotherapy.

Engineering an improved IgG4 molecule with reduced disulfide bond heterogeneity and increased Fab domain thermal stability.

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Peters, Shirley J; Smales, C Mark; Henry, Alistair J; Stephens, Paul E; West, Shauna; Humphreys, David P

2012-07-13

The integrity of antibody structure, stability, and biophysical characterization are becoming increasingly important as antibodies receive increasing scrutiny from regulatory authorities. We altered the disulfide bond arrangement of an IgG4 molecule by mutation of the Cys at the N terminus of the heavy chain constant domain 1 (C(H)1) (Kabat position 127) to a Ser and introduction of a Cys at a variety of positions (positions 227-230) at the C terminus of C(H)1. An inter-LC-C(H)1 disulfide bond is thus formed, which mimics the disulfide bond arrangement found in an IgG1 molecule. The antibody species present in the supernatant following transient expression in Chinese hamster ovary cells were analyzed by immunoblot to investigate product homogeneity, and purified product was analyzed by a thermofluor assay to determine thermal stability. We show that the light chain can form an inter-LC-C(H)1 disulfide bond with a Cys when present at several positions on the upper hinge (positions 227-230) and that such engineered disulfide bonds can consequently increase the Fab domain thermal stability between 3 and 6.8 °C. The IgG4 disulfide mutants displaying the greatest increase in Fab thermal stability were also the most homogeneous in terms of disulfide bond arrangement and antibody species present. Importantly, mutations did not affect the affinity for antigen of the resultant molecules. In combination with the previously described S241P mutation, we present an IgG4 molecule with increased Fab thermal stability and reduced product heterogeneity that potentially offers advantages for the production of IgG4 molecules.

Transmembrane and ubiquitin-like domain-containing protein 1 (Tmub1/HOPS facilitates surface expression of GluR2-containing AMPA receptors.

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Hyunjeong Yang

Full Text Available Some ubiquitin-like (UBL domain-containing proteins are known to play roles in receptor trafficking. Alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs undergo constitutive cycling between the intracellular compartment and the cell surface in the central nervous system. However, the function of UBL domain-containing proteins in the recycling of the AMPARs to the synaptic surface has not yet been reported.Here, we report that the Transmembrane and ubiquitin-like domain-containing 1 (Tmub1 protein, formerly known as the Hepatocyte Odd Protein Shuttling (HOPS protein, which is abundantly expressed in the brain and which exists in a synaptosomal membrane fraction, facilitates the recycling of the AMPAR subunit GluR2 to the cell surface. Neurons transfected with Tmub1/HOPS-RNAi plasmids showed a significant reduction in the AMPAR current as compared to their control neurons. Consistently, the synaptic surface expression of GluR2, but not of GluR1, was significantly decreased in the neurons transfected with the Tmub1/HOPS-RNAi and increased in the neurons overexpressing EGFP-Tmub1/HOPS. The altered surface expression of GluR2 was speculated to be due to the altered surface-recycling of the internalized GluR2 in our recycling assay. Eventually, we found that GluR2 and glutamate receptor interacting protein (GRIP were coimmunoprecipitated by the anti-Tmub1/HOPS antibody from the mouse brain. Taken together, these observations show that the Tmub1/HOPS plays a role in regulating basal synaptic transmission; it contributes to maintain the synaptic surface number of the GluR2-containing AMPARs by facilitating the recycling of GluR2 to the plasma membrane.

Type-specific IgG and IgA antibodies in old lymphogranuloma venerum determined by solid-phase radioimmunoassay

Energy Technology Data Exchange (ETDEWEB)

Meurman, O.; Terho, P.; Sonck, C.E.

1981-01-01

A solid-phase radioimmunoassay (RIA) using egg-grown purified Chlamydia trachomatis lymphogranuloma venereum (LGV) serotypes L1, L2, and L3 as antigen was used to measure type-specific IgG and IgA antibodies in sera of 36 patients who had contracted LGV infection about 40 years ago. The RIA test gave compatible results with the standard microimmunofluorescence test, and by RIA it was possible to identify the infecting serotype in 30 out of 36 patients studied. In 28 cases this was L2 and in two cases L1. Each patient had IgG antibodies and most of them (80%) IgA antibodies to at least one of the LGV serotypes. The antibody titers were still high 40 years after the acute infection, being higher than in male patients with a recent chlamydial urethritis. Highest antibody titers were detected in LGV patients who had a severe disease with intestinal involvement.

Type-specific IgG and IgA antibodies in old lymphogranuloma venerum determined by solid-phase radioimmunoassay

International Nuclear Information System (INIS)

Meurman, O.; Terho, P.; Sonck, C.E.

1981-01-01

A solid-phase radioimmunoassay (RIA) using egg-grown purified Chlamydia trachomatis lymphogranuloma venereum (LGV) serotypes L1, L2, and L3 as antigen was used to measure type-specific IgG and IgA antibodies in sera of 36 patients who had contracted LGV infection about 40 years ago. The RIA test gave compatible results with the standard microimmunofluorescence test, and by RIA it was possible to identify the infecting serotype in 30 out of 36 patients studied. In 28 cases this was L2 and in two cases L1. Each patient had IgG antibodies and most of them (80%) IgA antibodies to at least one of the LGV serotypes. The antibody titers were still high 40 years after the acute infection, being higher than in male patients with a recent chlamydial urethritis. Highest antibody titers were detected in LGV patients who had a severe disease with intestinal involvement. (orig.)

Human IgG1 Responses to Surface Localised Schistosoma mansoni Ly6 Family Members Drop following Praziquantel Treatment.

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Iain W Chalmers

Full Text Available The heptalaminate-covered, syncytial tegument is an important anatomical adaptation that enables schistosome parasites to maintain long-term, intravascular residence in definitive hosts. Investigation of the proteins present in this surface layer and the immune responses elicited by them during infection is crucial to our understanding of host/parasite interactions. Recent studies have revealed a number of novel tegumental surface proteins including three (SmCD59a, SmCD59b and Sm29 containing uPAR/Ly6 domains (renamed SmLy6A SmLy6B and SmLy6D in this study. While vaccination with SmLy6A (SmCD59a and SmLy6D (Sm29 induces protective immunity in experimental models, human immunoglobulin responses to representative SmLy6 family members have yet to be thoroughly explored.Using a PSI-BLAST-based search, we present a comprehensive reanalysis of the Schistosoma mansoni Ly6 family (SmLy6A-K. Our examination extends the number of members to eleven (including three novel proteins and provides strong evidence that the previously identified vaccine candidate Sm29 (renamed SmLy6D is a unique double uPAR/Ly6 domain-containing representative. Presence of canonical cysteine residues, signal peptides and GPI-anchor sites strongly suggest that all SmLy6 proteins are cell surface-bound. To provide evidence that SmLy6 members are immunogenic in human populations, we report IgG1 (as well as IgG4 and IgE responses against two surface-bound representatives (SmLy6A and SmLy6B within a cohort of S. mansoni-infected Ugandan males before and after praziquantel treatment. While pre-treatment IgG1 prevalence for SmLy6A and SmLy6B differs amongst the studied population (7.4% and 25.3% of the cohort, respectively, these values are both higher than IgG1 prevalence (2.7% for a sub-surface tegumental antigen, SmTAL1. Further, post-treatment IgG1 levels against surface-associated SmLy6A and SmLy6B significantly drop (p = 0.020 and p < 0.001, respectively when compared to rising Ig

Selection and characterization of naturally occurring single-domain (IgNAR) antibody fragments from immunized sharks by phage display.

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Dooley, Helen; Flajnik, Martin F; Porter, Andrew J

2003-09-01

The novel immunoglobulin isotype novel antigen receptor (IgNAR) is found in cartilaginous fish and is composed of a heavy-chain homodimer that does not associate with light chains. The variable regions of IgNAR function as independent domains similar to those found in the heavy-chain immunoglobulins of Camelids. Here, we describe the successful cloning and generation of a phage-displayed, single-domain library based upon the variable domain of IgNAR. Selection of such a library generated from nurse sharks (Ginglymostoma cirratum) immunized with the model antigen hen egg-white lysozyme (HEL) enabled the successful isolation of intact antigen-specific binders matured in vivo. The selected variable domains were shown to be functionally expressed in Escherichia coli, extremely stable, and bind to antigen specifically with an affinity in the nanomolar range. This approach can therefore be considered as an alternative route for the isolation of minimal antigen-binding fragments with favorable characteristics.

Dengue-1 envelope protein domain III along with PELC and CpG oligodeoxynucleotides synergistically enhances immune responses.

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Chen-Yi Chiang

Full Text Available The major weaknesses of subunit vaccines are their low immunogenicity and poor efficacy. Adjuvants can help to overcome some of these inherent defects with subunit vaccines. Here, we evaluated the efficacy of the newly developed water-in-oil-in-water multiphase emulsion system, termed PELC, in potentiating the protective capacity of dengue-1 envelope protein domain III. Unlike aluminum phosphate, dengue-1 envelope protein domain III formulated with PELC plus CpG oligodeoxynucleotides induced neutralizing antibodies against dengue-1 virus and increased the splenocyte secretion of IFN-γ after in vitro re-stimulation. The induced antibodies contained both the IgG1 and IgG2a subclasses. A rapid anamnestic neutralizing antibody response against a live dengue virus challenge was elicited at week 26 after the first immunization. These results demonstrate that PELC plus CpG oligodeoxynucleotides broaden the dengue-1 envelope protein domain III-specific immune responses. PELC plus CpG oligodeoxynucleotides is a promising adjuvant for recombinant protein based vaccination against dengue virus.

Temporal, Diagnostic, and Tissue-Specific Regulation of NRG3 Isoform Expression in Human Brain Development and Affective Disorders

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Paterson, Clare; Wang, Yanhong; Hyde, Thomas M.; Weinberger, Daniel R.; Kleinman, Joel E.; Law, Amanda J.

2018-01-01

Objective Genes implicated in schizophrenia are enriched in networks differentially regulated during human CNS development. Neuregulin 3 (NRG3), a brain-enriched neurotrophin, undergoes alternative splicing and is implicated in several neurological disorders with developmental origins. Isoform-specific increases in NRG3 are observed in schizophrenia and associated with rs10748842, a NRG3 risk polymorphism, suggesting NRG3 transcriptional dysregulation as a molecular mechanism of risk. The authors quantitatively mapped the temporal trajectories of NRG3 isoforms (classes I–IV) in the neocortex throughout the human lifespan, examined whether tissue-specific regulation of NRG3 occurs in humans, and determined if abnormalities in NRG3 transcriptomics occur in mood disorders and are genetically determined. Method NRG3 isoform classes I–IV were quantified using quantitative real-time polymerase chain reaction in human postmortem dorsolateral prefrontal cortex from 286 nonpsychiatric control individuals, from gestational week 14 to 85 years old, and individuals diagnosed with either bipolar disorder (N=34) or major depressive disorder (N=69). Tissue-specific mapping was investigated in several human tissues. rs10748842 was genotyped in individuals with mood disorders, and association with NRG3 isoform expression examined. Results NRG3 classes displayed individually specific expression trajectories across human neocortical development and aging; classes I, II, and IV were significantly associated with developmental stage. NRG3 class I was increased in bipolar and major depressive disorder, consistent with observations in schizophrenia. NRG3 class II was increased in bipolar disorder, and class III was increased in major depression. The rs10748842 risk genotype predicted elevated class II and III expression, consistent with previous reports in the brain, with tissue-specific analyses suggesting that classes II and III are brain-specific isoforms of NRG3. Conclusions

Tailor-making a protein a-derived domain for efficient site-specific photocoupling to Fc of mouse IgG₁.

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Feifan Yu

Full Text Available Affinity proteins binding to antibody constant regions have proved to be invaluable tools in biotechnology. Here, protein engineering was used to expand the repertoire of available immunoglobulin binding proteins via improvement of the binding strength between the widely used staphylococcal protein A-derived Z domain and the important immunoglobulin isotype mouse IgG₁ (mIgG₁. Addressing seven positions in the 58-residue three-helix bundle Z domain by single or double amino acid substitutions, a total of 170 variants were individually constructed, produced in E. coli and tested for binding to a set of mouse IgG₁ monoclonal antibodies (mAbs. The best variant, denoted Z(F5I corresponding to a Phe to Ile substitution at position 5, showed a typical ten-fold higher affinity than the wild-type as determined by biosensor technology. Eight amino acid positions in the Z(F5I variant were separately mutated to cysteine for incorporation of a photoactivable maleimide-benzophenone (MBP group as a probe for site-specific photoconjugation to Fc of mIgG₁, The best photocoupling efficiency to mIgG₁ Fc was seen when the MBP group was coupled to Cys at position 32, resulting in adduct formation to more than 60% of all heavy chains, with no observable non-selective conjugation to the light chains. A similar coupling yield was obtained for a panel of 19 different mIgG₁ mAbs, indicating a general characteristic. To exemplify functionalization of a mIgG₁ antibody via site-specific biotinylation, the Z(F5I-Q32C-MBP protein was first biotinylated using an amine reactive reagent and subsequently photoconjugated to an anti-human interferon-gamma mIgG₁ mAb. When comparing the specific antigen binding ability of the probe-biotinylated mAb to that of the directly biotinylated mAb, a significantly higher bioactivity was observed for the sample biotinylated using the Z(F5I-Q32C-MBP probe. This result indicates that the use of a site-specific and affinity probe

Combined roles of human IgG subclass, alternative complement pathway activation, and epitope density in the bactericidal activity of antibodies to meningococcal factor h binding protein.

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Giuntini, Serena; Reason, Donald C; Granoff, Dan M

2012-01-01

Meningococcal vaccines containing factor H binding protein (fHbp) are in clinical development. fHbp binds human fH, which enables the meningococcus to resist complement-mediated bacteriolysis. Previously, we found that chimeric human IgG1 mouse anti-fHbp monoclonal antibodies (MAbs) had human complement-mediated bactericidal activity only if the MAb inhibited fH binding. Since IgG subclasses differ in their ability to activate complement, we investigated the role of human IgG subclasses on antibody functional activity. We constructed chimeric MAbs in which three different murine fHbp-specific binding domains were each paired with human IgG1, IgG2, or IgG3. Against a wild-type group B isolate, all three IgG3 MAbs, irrespective of their ability to inhibit fH binding, had bactericidal activity that was >5-fold higher than the respective IgG1 MAbs, while the IgG2 MAbs had the least activity. Against a mutant with increased fHbp expression, the anti-fHbp MAbs elicited greater C4b deposition (classical pathway) and greater bactericidal activity than against the wild-type strain, and the IgG1 MAbs had similar or greater activity than the respective IgG3 MAbs. The bactericidal activity against both wild-type and mutant strains also was dependent, in part, on activation of the alternative complement pathway. Thus, at lower epitope density in the wild-type strain, the IgG3 anti-fHbp MAbs had the greatest bactericidal activity. At a higher epitope density in the mutant, the IgG1 MAbs had similar or greater bactericidal activity than the IgG3 MAbs, and the activity was less dependent on the inhibition of fH binding than at a lower epitope density.

Unprecedented multiplicity of Ig transmembrane and secretory mRNA forms in the cartilaginous fish.

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Rumfelt, Lynn L; Diaz, Marilyn; Lohr, Rebecca L; Mochon, Evonne; Flajnik, Martin F

2004-07-15

In most jawed vertebrates including cartilaginous fish, membrane-bound IgM is expressed as a five Ig superfamily (Igsf)-domain H chain attached to a transmembrane (Tm) region. Heretofore, bony fish IgM was the one exception with IgM mRNA spliced to produce a four-domain Tm H chain. We now demonstrate that the Tm and secretory (Sec) mRNAs of the novel cartilaginous fish Ig isotypes, IgW and IgNAR, are present in multiple forms, most likely generated by alternative splicing. In the nurse shark, Ginglymostoma cirratum, and horn shark, Heterodontus francisci, alternative splicing of Tm exons to the second or the fourth constant (C(H)) exons produces two distinct IgW Tm cDNAs. Although the seven-domain IgW Sec cDNA form contains a canonical secretory tail shared with IgM, IgNAR, and IgA, we report a three-domain cDNA form of shark IgW (IgW(short)) having an unusual Sec tail, which is orthologous to skate IgX(short) cDNA. The IgW and IgW(short) Sec transcripts are restricted in their tissue distribution and expression levels vary among individual sharks, with all forms expressed early in ontogeny. IgNAR mRNA is alternatively spliced to produce a truncated four-domain Tm cDNA and a second Tm cDNA is expressed identical in Igsf domains as the Sec form. PBL is enriched in the Tm cDNA of these Igs. These molecular data suggest that cartilaginous fish have augmented their humoral immune repertoire by diversifying the sizes of their Ig isotypes. Furthermore, these Tm cDNAs are prototypical and the truncated variants may translate as more stable protein at the cell surface.

Type 1 autoimmune pancreatitis.

Science.gov (United States)

Zen, Yoh; Bogdanos, Dimitrios P; Kawa, Shigeyuki

2011-12-07

Before the concept of autoimmune pancreatitis (AIP) was established, this form of pancreatitis had been recognized as lymphoplasmacytic sclerosing pancreatitis or non-alcoholic duct destructive chronic pancreatitis based on unique histological features. With the discovery in 2001 that serum IgG4 concentrations are specifically elevated in AIP patients, this emerging entity has been more widely accepted. Classical cases of AIP are now called type 1 as another distinct subtype (type 2 AIP) has been identified. Type 1 AIP, which accounts for 2% of chronic pancreatitis cases, predominantly affects adult males. Patients usually present with obstructive jaundice due to enlargement of the pancreatic head or thickening of the lower bile duct wall. Pancreatic cancer is the leading differential diagnosis for which serological, imaging, and histological examinations need to be considered. Serologically, an elevated level of IgG4 is the most sensitive and specific finding. Imaging features include irregular narrowing of the pancreatic duct, diffuse or focal enlargement of the pancreas, a peri-pancreatic capsule-like rim, and enhancement at the late phase of contrast-enhanced images. Biopsy or surgical specimens show diffuse lymphoplasmacytic infiltration containing many IgG4+ plasma cells, storiform fibrosis, and obliterative phlebitis. A dramatic response to steroid therapy is another characteristic, and serological or radiological effects are normally identified within the first 2 or 3 weeks. Type 1 AIP is estimated as a pancreatic manifestation of systemic IgG4-related disease based on the fact that synchronous or metachronous lesions can develop in multiple organs (e.g. bile duct, salivary/lacrimal glands, retroperitoneum, artery, lung, and kidney) and those lesions are histologically identical irrespective of the organ of origin. Several potential autoantigens have been identified so far. A Th2-dominant immune reaction and the activation of regulatory T-cells are assumed

Type 1 autoimmune pancreatitis

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Zen Yoh

2011-12-01

Full Text Available Abstract Before the concept of autoimmune pancreatitis (AIP was established, this form of pancreatitis had been recognized as lymphoplasmacytic sclerosing pancreatitis or non-alcoholic duct destructive chronic pancreatitis based on unique histological features. With the discovery in 2001 that serum IgG4 concentrations are specifically elevated in AIP patients, this emerging entity has been more widely accepted. Classical cases of AIP are now called type 1 as another distinct subtype (type 2 AIP has been identified. Type 1 AIP, which accounts for 2% of chronic pancreatitis cases, predominantly affects adult males. Patients usually present with obstructive jaundice due to enlargement of the pancreatic head or thickening of the lower bile duct wall. Pancreatic cancer is the leading differential diagnosis for which serological, imaging, and histological examinations need to be considered. Serologically, an elevated level of IgG4 is the most sensitive and specific finding. Imaging features include irregular narrowing of the pancreatic duct, diffuse or focal enlargement of the pancreas, a peri-pancreatic capsule-like rim, and enhancement at the late phase of contrast-enhanced images. Biopsy or surgical specimens show diffuse lymphoplasmacytic infiltration containing many IgG4+ plasma cells, storiform fibrosis, and obliterative phlebitis. A dramatic response to steroid therapy is another characteristic, and serological or radiological effects are normally identified within the first 2 or 3 weeks. Type 1 AIP is estimated as a pancreatic manifestation of systemic IgG4-related disease based on the fact that synchronous or metachronous lesions can develop in multiple organs (e.g. bile duct, salivary/lacrimal glands, retroperitoneum, artery, lung, and kidney and those lesions are histologically identical irrespective of the organ of origin. Several potential autoantigens have been identified so far. A Th2-dominant immune reaction and the activation of

Circulating immune complexes, immunoglobulin classes (IgG, IgA ...

African Journals Online (AJOL)

Objective:- To evaluate serum levels of circulating immune complexes (CICs), immunoglobulin classes (IgG, IgA and IgM) and Complement Components (C3c, C4 and Factor B) in Nigerians with Type 1 or Type 2 diabetes mellitus. Design:- Case control study. Setting:- University College Hospital, Ibadan, Oyo State, Nigeria.

V-set and Ig domain-containing 4 (VSIG4)-expressing hepatic F4/80+ cells regulate oral antigen-specific responses in mouse.

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Shin, Wonhwa; Jeon, Youkyoung; Choi, Inhak; Kim, Yeon-Jeong

2018-04-01

Oral tolerance can prevent unnecessary immune responses against dietary antigens. Members of the B7 protein family play critical roles in the positive and/or negative regulation of T cell responses to interactions between APCs and T cells. V-set and Ig domain-containing 4 (VSIG4), a B7-related co-signaling molecule, has been known to act as a co-inhibitory ligand and may be critical in establishing immune tolerance. Therefore, we investigated the regulation of VSIG4 signaling in a food allergy and experimental oral tolerance murine models. We analyzed the contributions of the two main sites involved in oral tolerance, the mesenteric lymph node (MLN) and the liver, in VSIG4-mediated oral tolerance induction. Through the comparative analysis of major APCs, dendritic cells (DCs) and macrophages, we found that Kupffer cells play a critical role in inducing regulatory T cells (Tregs) and establishing immune tolerance against oral antigens via VSIG4 signaling. Taken together, these results suggest the possibility of VSIG4 signaling-based regulation of orally administered antigens. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Selection of cholera toxin specific IgNAR single-domain antibodies from a naïve shark library.

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Liu, Jinny L; Anderson, George P; Delehanty, James B; Baumann, Richard; Hayhurst, Andrew; Goldman, Ellen R

2007-03-01

Shark immunoglobulin new antigen receptor (IgNAR, also referred to as NAR) variable domains (Vs) are single-domain antibody (sdAb) fragments containing only two hypervariable loop structures forming 3D topologies for a wide range of antigen recognition and binding. Their small size ( approximately 12kDa) and high solubility, thermostability and binding specificity make IgNARs an exceptional alternative source of engineered antibodies for sensor applications. Here, two new shark NAR V display libraries containing >10(7) unique clones from non-immunized (naïve) adult spiny dogfish (Squalus acanthias) and smooth dogfish (Mustelus canis) sharks were constructed. The most conserved consensus sequences derived from random clone sequence were compared with published nurse shark (Ginglymostoma cirratum) sequences. Cholera toxin (CT) was chosen for panning one of the naïve display libraries due to its severe pathogenicity and commercial availability. Three very similar CT binders were selected and purified soluble monomeric anti-CT sdAbs were characterized using Luminex(100) and traditional ELISA assays. These novel anti-CT sdAbs selected from our newly constructed shark NAR V sdAb library specifically bound to soluble antigen, without cross reacting with other irrelevant antigens. They also showed superior heat stability, exhibiting slow loss of activity over the course of one hour at high temperature (95 degrees C), while conventional antibodies lost all activity in the first 5-10min. The successful isolation of target specific sdAbs from one of our non-biased NAR libraries, demonstrate their ability to provide binders against an unacquainted antigen of interest.

Autoimmune responses in patients with linear IgA bullous dermatosis: both autoantibodies and T lymphocytes recognize the NC16A domain of the BP180 molecule.

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Lin, Mong-Shang; Fu, Chang-Ling; Olague-Marchan, Monica; Hacker, Mary K; Zillikens, Detlef; Giudice, George J; Fairley, Janet A

2002-03-01

Linear IgA bullous disease (LABD) is an autoimmune skin disease characterized by subepidermal blisters and IgA autoantibodies directed against the epidermal basement membrane zone (BMZ) of the skin. Various antigens have been identified as targets of IgA autoantibodies including BP180, a type II glycoprotein that spans the BMZ and lamina lucida. Previously, we have identified a subset of LABD patients whose sera contained IgA antibodies against the 16th noncollagenous (NC16A) domain of BP180. NC16A was previously shown to harbor epitopes that are recognized by both autoantibodies and T cells from patients with bullous pemphigoid and herpes gestationis and is thought to be associated with the development of these immunobullous diseases. The aim of this study was to determine whether T lymphocytes from LABD patients with anti-NC16A IgA autoantibodies respond to epitopes in the same region of the BP180 protein. Indeed, of the four LABD patients in our study, all had T cells that specifically proliferated in response to NC16A. Moreover, two subfragments of NC16A were identified as the predominant targets of LABD T cells. Further analysis of T cell lines and clones derived from these patients revealed that these cells express a CD4 memory T cell phenotype and secrete a Th1/Th2 mixed-cytokine profile, characteristics similar to those of T cells in bullous pemphigoid patients. Our data suggest that the BP180 protein, typically the NC16A region, is the common target of both cellular and humoral immune responses in some LABD patients. This information helps to further elucidate the autoimmune mechanisms in this disease.

Recurrent Skin and Lung Infections in Autosomal Dominant Hyper IgE Syndrome with Transactivation Domain STAT3 Mutation

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Chad J. Cooper

2014-01-01

Full Text Available Background. Hyper IgE is a rare systemic disease characterized by the clinical triad of high serum levels of IgE (>2000 IU/mL, eczema, and recurrent staphylococcal skin and lung infections. The presentation of hyper IgE syndrome is highly variable, which makes it easy to confuse the diagnosis with that of severe atopy or other rare immunodeficiency disorders. Case Report. A 23-year-old Hispanic presented with history of frequent respiratory and gastrointestinal infections as a child and multiple episodes of skin and lung infections (abscess with Staphylococcus aureus throughout his adult life. He had multiple eczematous lesions and folliculitis over his entire body, oral/esophageal candidiasis, and retention of his primary teeth. The IgE was elevated (>5000 IU/mL. Genetic mutation analysis revealed a mutation affecting the transactivation domain of the STAT3 gene. Conclusion. The hallmark of hyper IgE syndrome is serum IgE of >2000 IU/mL. Hyper IgE syndrome is a genetic disorder that is either autosomal dominant or recessive. A definite diagnosis can be made with genetic mutation analysis, and in this case, it revealed a very rare finding of the transactivation domain STAT3 mutation. Hyper IgE syndrome is a challenge for clinicians in establishing a diagnosis in suspected cases.

Expression, crystallization and preliminary crystallographic analysis of the extracellular IgV-like domain of the human natural killer cell inhibitory receptor p75/AIRM1.

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Dimasi, Nazzareno; Moretta, Lorenzo; Biassoni, Roberto; Mariuzza, Roy A

2003-10-01

p75/AIRM1 (Siglec-7) is a sialic acid-binding Ig-like lectin recently identified as an inhibitory receptor on natural killer cells. The expression, in vitro folding, circular-dichroism spectroscopy, crystallization and preliminary X-ray characterization of the Ig-V like domain of p75/AIRM1 are reported. X-ray data were collected from a single crystal at 100 K, with a maximum useful diffraction pattern extending to 1.45 A resolution on a synchrotron source. The crystal belongs to a primitive monoclinic space group, with unit-cell parameters a = 32.65, b = 49.72, c = 39.79 A, alpha = gamma = 90, beta = 113 degrees. The systematic absences indicate that the space group is P2(1). Assuming one molecule per asymmetric unit, V(M) (the Matthews coefficient) was calculated to be 1.879 A(3) Da(-1) and the solvent content was estimated to be 32.01%.

Stability assessment on a library scale: a rapid method for the evaluation of the commutability and insertion of residues in C-terminal loops of the CH3 domains of IgG1-Fc.

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Hasenhindl, Christoph; Traxlmayr, Michael W; Wozniak-Knopp, Gordana; Jones, Phil C; Stadlmayr, Gerhard; Rüker, Florian; Obinger, Christian

2013-10-01

Antigen-binding Fc fragments (Fcab) are generated by engineering the C-terminal loop regions in the CH3 domain of human immunoglobulin G class 1-crystallizable fragment (IgG1-Fc). For an optimum library design with high percentage of well-folded clones for efficient binder selection, information about the correlation between primary structure and stability is needed. Here, we present a rapid method that allows determination of the overall stability of whole libraries of IgG1-Fc on the surface of yeast by flow cytometry. Libraries of IgG1-Fc mutants with distinct regions in AB-, CD- and EF-loops of the CH3 domains randomized or carrying therein insertions of five additional residues were constructed, incubated at increasing temperatures and probed for residual binding of generic Fc ligands. Calculated temperatures of half-maximal irreversible denaturation of the libraries gave a clear hierarchy of tolerance to randomization of distinct loop positions. Experimental data were evaluated by a computational approach and are discussed with respect to the structure of IgG1-Fc and variation in sequence and length of these loops in homologous Fc proteins. Generally, the described method allows for quick assessment of the effects of randomization of distinct regions on the foldability and stability of a yeast-displayed protein library.

NRG -agressiivne kasvuettevõte / Romet Kreek

Index Scriptorium Estoniae

Kreek, Romet, 1972-

2001-01-01

Ilmunud ka: Delovõje Vedomosti 12. sept., lk. 33. NRG Energy on võtnud eesmärgiks kasvatada 2005.a. lõpuks enda omanduses olevad tootmisvõimsused 50 000 MW-le, mis tähendab vähemalt 25% kasvu igal aastal. Tabelid. Diagramm

Potent neutralizing serum immunoglobulin A (IgA) in human immunodeficiency virus type 2-exposed IgG-seronegative individuals

DEFF Research Database (Denmark)

Lizeng, Q; Nilsson, C; Sourial, S

2004-01-01

Links Potent neutralizing serum immunoglobulin A (IgA) in human immunodeficiency virus type 2-exposed IgG-seronegative individuals.Lizeng Q, Nilsson C, Sourial S, Andersson S, Larsen O, Aaby P, Ehnlund M, Bjorling E. Research Center, South Hospital, Stockholm, Sweden. The mechanisms behind...... the resistance to human immunodeficiency virus type 2 (HIV-2) infection are still not fully understood. In the present study, we explored the HIV-2-specific humoral serum immunoglobulin A (IgA) immune response in HIV-2-exposed IgG-seronegative (EGSN) individuals. Serum samples from heterosexual EGSN individuals...... and their known HIV-2-infected partners, as well as controls originating from Guinea-Bissau in Africa, were studied. Antibody reactivity to native and recombinant envelope glycoproteins was investigated, and the capacity of purified serum IgA to neutralize HIV-2(SBL6669) was tested. Our results showed that 16...

A novel IgA-like immunoglobulin in the reptile Eublepharis macularius.

Science.gov (United States)

Deza, Francisco Gambón; Espinel, Christian Sánchez; Beneitez, Julio Valdueza

2007-01-01

The appearance of antibody genes over evolution coincided with the origin of the vertebrates. Reptiles are of great interest in evolution since they are the link between the amphibians, birds, and mammals. This work describes the presence of a gene in the reptile leopard gecko (Eublepharis macularius) where phylogenetic studies suggest that it is the gene orthologue of immunoglobulin A (IgA) and immunoglobulin X (IgX) in Xenopus. Messenger RNA samples taken from different tissues showed expression of this antibody in intestinal tissue. Data on the structure deduced from the sequence of nucleotides showed an antibody with four domains in the constant region. There is a sequence of 20 amino acids in the C terminus similar to the secretory tail of immunoglobulin M (IgM) and IgA. A detailed analysis of the sequence of amino acids displayed a paradox, i.e., domains CH1 and CH2 showed a clear homology with domains CH1 and CH2 of immunoglobulin Y (IgY) while domains CH3 and CH4 were homologous with domains CH3 and CH4 of IgM. This homology pattern is also seen in Xenopus IgX and bird IgA. The most logical explanation for this phenomenon is that a recombination between the IgM and IgY gave rise to the IgA.

NC1 domain of type VII collagen binds to the beta3 chain of laminin 5 via a unique subdomain within the fibronectin-like repeats.

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Chen, M; Marinkovich, M P; Jones, J C; O'Toole, E A; Li, Y Y; Woodley, D T

1999-02-01

Type VII collagen, the major component of anchoring fibrils, consists of a central collagenous triple-helical domain flanked by two noncollagenous, globular domains, NC1 and NC2. Approximately 50% of the molecular mass of the molecule is consumed by the NC1 domain. We previously demonstrated that NC1 binds to various extracellular matrix components including a complex of laminin 5 and laminin 6 (Chen et al, 1997a). In this study, we examined the interaction of NC1 with laminin 5 (a component of anchoring filaments). Both authentic and purified recombinant NC1 bound to human and rat laminin 5 as measured by enzyme-linked immunosorbant assay and by binding of 125I-radiolabeled NC1 to laminin 5-coated wells, but not to laminin 1 or albumin. NC1 bound predominantly to the beta3 chain of laminin 5, but also to the gamma2 chain when examined by a protein overlay assay. The binding of 125I-NC1 to laminin 5 was inhibited by a 50-fold excess of unlabeled NC1 or de-glycosylated NC1, as well as a polyclonal antibody to laminin 5 or a monoclonal antibody to the beta3 chain. In contrast, the NC1-laminin 5 interaction was not affected by a monoclonal antibody to the alpha3 chain. Using NC1 deletion mutant recombinant proteins, a 285 AA (residues 760-1045) subdomain of NC1 was identified as the binding site for laminin 5. IgG from an epidermolysis bullosa acquisita serum containing autoantibodies to epitopes within NC1 that colocalized with the laminin 5 binding site inhibited the binding of NC1 to laminin 5. Thus, perturbation of the NC1-laminin 5 interaction may contribute to the pathogenesis of epidermolysis bullosa acquisita.

Cord blood IgE. I. IgE screening in 2814 newborn children

DEFF Research Database (Denmark)

Hansen, L G; Høst, A; Halken, S

1992-01-01

Screening of total IgE in 2814 cord blood samples was analysed by Phadebas IgE PRIST in 2 1-year birth cohorts (1983-1984 and 1985-1986) in Denmark (n = 1189 + 1625). 48.6% of the sera contained less IgE than the detection limit 0.1 kU/l. Cord blood IgE values greater than or equal to 0.5 kU/l we...

Dissection of the IgNAR V domain: molecular scanning and orthologue database mining define novel IgNAR hallmarks and affinity maturation mechanisms.

Science.gov (United States)

Fennell, B J; Darmanin-Sheehan, A; Hufton, S E; Calabro, V; Wu, L; Müller, M R; Cao, W; Gill, D; Cunningham, O; Finlay, W J J

2010-07-09

The shark antigen-binding V(NAR) domain has the potential to provide an attractive alternative to traditional biotherapeutics based on its small size, advantageous physiochemical properties, and unusual ability to target clefts in enzymes or cell surface molecules. The V(NAR) shares many of the properties of the well-characterised single-domain camelid V(H)H but is much less understood at the molecular level. We chose the hen-egg-lysozyme-specific archetypal Type I V(NAR) 5A7 and used ribosome display in combination with error-prone mutagenesis to interrogate the entire sequence space. We found a high level of mutational plasticity across the V(NAR) domain, particularly within the framework 2 and hypervariable region 2 regions. A number of residues important for affinity were identified, and a triple mutant combining A1D, S61R, and G62R resulted in a K(D) of 460 pM for hen egg lysozyme, a 20-fold improvement over wild-type 5A7, and the highest K(D) yet reported for V(NAR)-antigen interactions. These findings were rationalised using structural modelling and indicate the importance of residues outside the classical complementarity determining regions in making novel antigen contacts that modulate affinity. We also located two solvent-exposed residues (G15 and G42), distant from the V(NAR) paratope, which retain function upon mutation to cysteine and have the potential to be exploited as sites for targeted covalent modification. Our findings with 5A7 were extended to all known NAR structures using an in-depth bioinformatic analysis of sequence data available in the literature and a newly generated V(NAR) database. This study allowed us to identify, for the first time, both V(NAR)-specific and V(NAR)/Ig V(L)/TCR V(alpha) overlapping hallmark residues, which are critical for the structural and functional integrity of the single domain. Intriguingly, each of our designated V(NAR)-specific hallmarks align precisely with previously defined mutational 'cold spots' in

A Human Antibody That Binds to the Sixth Ig-Like Domain of VCAM-1 Blocks Lung Cancer Cell Migration In Vitro

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Mi Ra Kim

2017-03-01

Full Text Available Vascular cell adhesion molecule-1 (VCAM-1 is closely associated with tumor progression and metastasis. However, the relevance and role of VCAM-1 in lung cancer have not been clearly elucidated. In this study, we found that VCAM-1 was highly overexpressed in lung cancer tissue compared with that of normal lung tissue, and high VCAM-1 expression correlated with poor survival in lung cancer patients. VCAM-1 knockdown reduced migration of A549 human lung cancer cells into Matrigel, and competitive blocking experiments targeting the Ig-like domain 6 of VCAM-1 (VCAM-1-D6 demonstrated that the VCAM-1-D6 domain was critical for VCAM-1 mediated A549 cell migration into Matrigel. Next, we developed a human monoclonal antibody specific to human and mouse VCAM-1-D6 (VCAM-1-D6 huMab, which was isolated from a human synthetic antibody library using phage display technology. Finally, we showed that VCAM-1-D6 huMab had a nanomolar affinity for VCAM-1-D6 and that it potently suppressed the migration of A549 and NCI-H1299 lung cancer cell lines into Matrigel. Taken together, these results suggest that VCAM-1-D6 is a key domain for regulating VCAM-1-mediated lung cancer invasion and that our newly developed VCAM-1-D6 huMab will be a useful tool for inhibiting VCAM-1-expressing lung cancer cell invasion.

eCD4-Ig promotes ADCC activity of sera from HIV-1-infected patients.

Directory of Open Access Journals (Sweden)

Meredith E Davis-Gardner

2017-12-01

Full Text Available Antibody-dependent cell-mediated cytotoxity (ADCC can eliminate HIV-1 infected cells, and may help reduce the reservoir of latent virus in infected patients. Sera of HIV-1 positive individuals include a number of antibodies that recognize epitopes usually occluded on HIV-1 envelope glycoprotein (Env trimers. We have recently described eCD4-Ig, a potent and exceptionally broad inhibitor of HIV-1 entry that can be used to protect rhesus macaques from multiple high-dose challenges with simian-human immunodeficiency virus AD8 (SHIV-AD8. Here we show that eCD4-Ig bearing an IgG1 Fc domain (eCD4-IgG1 can mediate efficient ADCC activity against HIV-1 isolates with differing tropisms, and that it does so at least 10-fold more efficiently than CD4-Ig, even when more CD4-Ig molecules bound cell surface-expressed Env. An ADCC-inactive IgG2 form of eCD4-Ig (eCD4-IgG2 exposes V3-loop and CD4-induced epitopes on cell-expressed trimers, and renders HIV-1-infected cells susceptible to ADCC mediated by antibodies of these classes. Moreover, eCD4-IgG2, but not IgG2 forms of the broadly neutralizing antibodies VRC01 and 10-1074, enhances the ADCC activities of serum antibodies from patients by 100-fold, and significantly enhanced killing of two latently infected T-cell lines reactivated by vorinostat or TNFα. Thus eCD4-Ig is qualitatively different from CD4-Ig or neutralizing antibodies in its ability to mediate ADCC, and it may be uniquely useful in treating HIV-1 infection or reducing the reservoir of latently infected cells.

Immunohistochemical analysis of IgA expression differentiates IgG4-related disease from plasma cell-type Castleman disease.

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Manabe, Akihiro; Igawa, Takuro; Takeuchi, Mai; Gion, Yuka; Yoshino, Tadashi; Sato, Yasuharu

2017-03-01

Plasma cell-type Castleman disease (PCD) is often encountered when differentiating IgG4-related disease (IgG4-RD). Given that serum IgA is often elevated in Castleman disease, we investigated whether IgA expression levels in histological specimens can be used to differentiate between the two diseases. Lymph node lesions obtained from 12 IgG4-RD and 11 PCD patients were analysed by immunohistochemistry with anti-IgG, -IgG4, and -IgA antibodies. In addition to all 12 cases of IgG4-RD, 8/11 cases (72.7 %) of PCD also met the diagnostic criteria of IgG4-RD (serum IgG4 ≥135 mg/dl and IgG4/IgG-positive cells ≥40 %). IgA-positive cells were sparsely and densely distributed in IgG4-RD and PCD cases, respectively. The median number of IgA-positive cells ± SD in all 12 cases of IgG4-RD was 31 ± 37 cells per three high-powered fields (3HPFs) (range 4-118 cells/3HPFs). In contrast, the median number of IgA-positive cells, which was significantly higher in all 11 cases of PCD, was 303 ± 238 cells/3HPFs (range 74-737 cells/3HPFs) (P IgG4-RD.

Crystallographic characterization of the radixin FERM domain bound to the cytoplasmic tail of membrane-type 1 matrix metalloproteinase (MT1-MMP)

International Nuclear Information System (INIS)

Terawaki, Shin-ichi; Kitano, Ken; Aoyama, Miki; Hakoshima, Toshio

2008-01-01

The radixin FERM domain was shown to bind the MT1-MMP cytoplasmic peptide and crystals of the complex were obtained. ERM proteins play a role in the cross-linking found between plasma membranes and actin filaments. The N-terminal FERM domains of ERM proteins are responsible for membrane association through direct interaction with the cytoplasmic tails of integral membrane proteins. During cell migration and movement, membrane-type 1 matrix metalloproteinase (MT1-MMP) on plasma membranes sheds adhesion molecule CD44 in addition to degrading the extracellular matrix. Here, the interaction between the radixin FERM domain and the MT1-MMP cytoplasmic tail is reported and preliminary crystallographic characterization of crystals of the radixin FERM domain bound to the cytoplasmic tail of MT1-MMP is presented. The crystals belong to space group P6 1 22, with unit-cell parameters a = b = 122.7, c = 128.3 Å, and contain one complex in the crystallographic asymmetric unit. The diffraction data were collected to a resolution of 2.4 Å

Modulation of the Neuregulin 1/ErbB system after skeletal muscle denervation and reinnervation.

Science.gov (United States)

Morano, Michela; Ronchi, Giulia; Nicolò, Valentina; Fornasari, Benedetta Elena; Crosio, Alessandro; Perroteau, Isabelle; Geuna, Stefano; Gambarotta, Giovanna; Raimondo, Stefania

2018-03-22

Neuregulin 1 (NRG1) is a growth factor produced by both peripheral nerves and skeletal muscle. In muscle, it regulates neuromuscular junction gene expression, acetylcholine receptor number, muscle homeostasis and satellite cell survival. NRG1 signalling is mediated by the tyrosine kinase receptors ErbB3 and ErbB4 and their co-receptors ErbB1 and ErbB2. The NRG1/ErbB system is well studied in nerve tissue after injury, but little is known about this system in skeletal muscle after denervation/reinnervation processes. Here, we performed a detailed time-course expression analysis of several NRG1 isoforms and ErbB receptors in the rat superficial digitorum flexor muscle after three types of median nerve injuries of different severities. We found that ErbB receptor expression was correlated with the innervated state of the muscle, with upregulation of ErbB2 clearly associated with the denervation state. Interestingly, the NRG1 isoforms were differently regulated depending on the nerve injury type, leading to the hypothesis that both the NRG1α and NRG1β isoforms play a key role in the muscle reaction to injury. Indeed, in vitro experiments with C2C12 atrophic myotubes revealed that both NRG1α and NRG1β treatment influences the best-known atrophic pathways, suggesting that NRG1 might play an anti-atrophic role.

Anti-PGL1 salivary IgA/IgM, serum IgG/IgM, and nasal Mycobacterium leprae DNA in individuals with household contact with leprosy.

Science.gov (United States)

Brito e Cabral, Paula; Júnior, José Evandro Cunha; de Macedo, Alexandre Casimiro; Alves, Alexandre Rodrigues; Gonçalves, Thially Braga; Brito e Cabral, Tereza Cristina; Gondim, Ana Paula Soares; Pinto, Maria Isabel Moraes; Oseki, Karen Tubono; Camara, Lilia Maria Carneiro; Rabenhorst, Silvia Helena Barem; Nagao-Dias, Aparecida Tiemi

2013-11-01

Leprosy household contacts represent a group at high risk of developing the disease. The aim of this study was to detect Mycobacterium leprae subclinical infection in this group through serological and molecular parameters. Serum anti-PGL1 IgG/IgM and salivary anti-PGL1 IgA/IgM was investigated using an ELISA, and nasal carriage of M. leprae DNA was detected by PCR, in leprosy household contacts of paucibacillary (PB) and multibacillary (MB) household leprosy patients (n=135), their index cases (n=30), and in persons living in a low endemic city (n=17). Salivary anti-PGL1 IgA and IgM and serum anti-PGL1 IgG showed good correlation comparing contacts and index cases (p0.05). A high frequency of anti-PGL1 IgM positivity was found in IgG-negative samples (pleprae DNA was found in the nasal swabs of nine out of the 85 MB household leprosy contacts (10.6%) and in three out of the 50 PB household leprosy contacts (6.0%). We strongly suggest that serum IgG/IgM and salivary anti-PGL1 IgA/IgM measurements are used to follow leprosy household contacts. Copyright © 2013 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Association of IgG co-deposition with serum levels of galactose-deficient IgA1 in pediatric IgA nephropathy

Science.gov (United States)

Eison, T. Matthew; Hastings, M. Colleen; Moldoveanu, Zina; Sanders, John T.; Gaber, Lillian; Walker, Patrick D.; Lau, Keith K; Julian, Bruce A.; Novak, Jan; Wyatt, Robert J.

2012-01-01

Objective: To determine whether the absence of mesangial IgG deposits is associated with the absence of elevated blood levels of galactose-deficient IgA1 (Gd-IgA1) in pediatric patients with IgA nephropathy (IgAN). Design and methods: Serum Gd-IgA1 levels were determined by ELISA using an N-acetylgalactosamine-specific lectin from Helix aspersa. Levels of Gd-IgA1 above the 90th percentile for healthy pediatric controls were considered to be elevated. Renal biopsy samples were examined by immunofluorescence for presence and intensity of staining for IgA, IgG, IgM, C3 and C1q and by light microscopy for histological changes. Findings were graded by a single pathologist (L. Gaber) at UTHSC until 2007 and by NephropathTM (Little Rock, AR, USA) thereafter. Staining for the mesangial deposits was considered negative when intensity was trace or less, and positive at greater intensity. Fisher’s exact-test was used to determine significance of 2 × 2 tables. Results: Serum samples were obtained from 30 patients with IgAN diagnosed before age 18 years. Male : female ratio was 2.3 : 1. Twenty were Caucasian and 10 were African-American. Blood was obtained within 3 months of biopsy (incident cases) for 12, while 18 provided blood > 3 months after biopsy (prevalent cases). Serum Gd-IgA1 level was elevated in 23 (77%) of cases and 20 (67%) had a biopsy positive for IgG. Of those 20 patients, 18 (90%) had an elevated serum Gd-IgA1 level, whereas 5 (50%) of patients with biopsies without IgG had a normal serum Gd-IgA1 level (p = 0.026). Summary: In this small study we found a weak association between the absence of IgG in the biopsy and normal serum Gd-IgA1 level. PMID:23006340

Purification, crystallization and preliminary X-ray analysis of the IgV domain of human nectin-4.

Science.gov (United States)

Xu, Xiang; Zhang, Xiaoai; Lu, Guangwen; Cai, Yongping

2012-08-01

Nectin-4 belongs to a family of immunoglobulin-like cell adhesion molecules and is highly expressed in cancer cells. Recently, nectin-4 was found to be a receptor of measles virus and the IgV domain sustains strong binding to measles virus H protein. In this study, the successful expression and purification of human nectin-4 V domain (nectin-4v) is reported. The purified protein was crystallized using the sitting-drop vapour-diffusion method. The crystals diffracted to 1.8 Å resolution and belonged to space group P2(1), with unit-cell parameters a = 33.1, b = 51.7, c = 56.9 Å, β = 94.7°. Preliminary analysis of the diffraction data was also performed.

Reactivities of N-acetylgalactosamine-specific lectins with human IgA1 proteins

DEFF Research Database (Denmark)

Moore, J.S.; Kulhavy, R.; Tomana, M.

2007-01-01

, VV reacted with sugars of both IgA subclasses and IgG, indicating that it also recognized N-linked glycans without GalNAc. Furthermore, HAA and HPA from several manufacturers differed in their ability to bind various IgA1 myeloma proteins and other GalNAc-containing glycoproteins in ELISA and Western...

The absence of serum IgE antibodies indicates non-type 2 disease in young asthmatics.

Science.gov (United States)

Tsolakis, N; Malinovschi, A; Nordvall, L; Janson, C; Borres, M P; Alving, K

2018-06-01

Atopic asthma is associated with elevated type-2 biomarkers such as fraction of exhaled nitric oxide (FeNO) and blood eosinophil (B-Eos) count. However, increased type 2 markers have also been reported in traditionally defined non-atopic asthma. To determine a clinically useful level of IgE sensitization for ruling out type 2 asthma. Asthmatics (N = 408; age 10-35 years) were analysed using the multi-allergen tests Phadiatop and fx5 (ImmunoCAP). Subjects were grouped based on IgE-antibody concentrations: ≥0.35 kU A /L for at least one test (n = 326) or <0.35 kU A /L for both tests (n = 82). Τhe latter group was subsequently divided into 2 groups: IgE 0.10-0.34 kU A /L (n = 34) and IgE < 0.10 kU A /L (n = 48). The relationships between type 2 biomarkers, and inadequate asthma control (ACT < 20), reduced lung function (FEV 1  < 80%), recent asthma attacks and airway hyperresponsiveness (AHR) to methacholine were determined. In univariate analyses, at least one type 2 marker related to each asthma outcome in subjects with IgE ≥0.35 kU A /L. In subjects with IgE 0.10-0.34 kU A /L, elevated FeNO related to reduced lung function (P = .008) and B-Eos to AHR (P = .03). No associations were found in subjects with IgE < 0.10 kU A /L. In multivariate analysis, a relationship between FeNO and reduced lung function remained in subjects with IgE < 0.35 kU A /L (P = .03). Clinically relevant elevation of type 2 biomarkers was seen in young asthmatics with IgE antibodies <0.35 kU A /L, but not those with IgE < 0.10 kU A /L. It seems possible to define non-type 2 asthma through sensitive IgE-antibody measurement. © 2018 John Wiley & Sons Ltd.

IgE, IgG4 and IgA specific to Bet v 1-related food allergens do not predict oral allergy syndrome.

Science.gov (United States)

Guhsl, E E; Hofstetter, G; Lengger, N; Hemmer, W; Ebner, C; Fröschl, R; Bublin, M; Lupinek, C; Breiteneder, H; Radauer, C

2015-01-01

Birch pollen-associated plant food allergy is caused by Bet v 1-specific IgE, but presence of cross-reactive IgE to related allergens does not predict food allergy. The role of other immunoglobulin isotypes in the birch pollen-plant food syndrome has not been investigated in detail. Bet v 1-sensitized birch pollen-allergic patients (n = 35) were diagnosed for food allergy by standardized interviews, skin prick tests, prick-to-prick tests and ImmunoCAP. Concentrations of allergen-specific IgE, IgG1, IgG4 and IgA to seven Bet v 1-related food allergens were determined by ELISA. Bet v 1, Cor a 1, Mal d 1 and Pru p 1 bound IgE from all and IgG4 and IgA from the majority of sera. Immunoglobulins to Gly m 4, Vig r 1 and Api g 1.01 were detected in allergy and increased or reduced levels of IgE, IgG1, IgG4 or IgA specific to most Bet v 1-related allergens. Api g 1-specific IgE was significantly (P = 0.01) elevated in celeriac-allergic compared with celeriac-tolerant patients. Likewise, frequencies of IgE (71% vs 15%; P = 0.01) and IgA (86% vs 38%; P = 0.04) binding to Api g 1.01 were increased. Measurements of allergen-specific immunoglobulins are not suitable for diagnosing Bet v 1-mediated plant food allergy to hazelnut and Rosaceae fruits. In contrast, IgE and IgA to the distantly related allergen Api g 1 correlate with allergy to celeriac. © 2014 The Authors. Allergy Published by John Wiley & Sons Ltd.

Circulating IgA immune complexes in patients with psoriasis

International Nuclear Information System (INIS)

Hall, R.P.; Peck, G.L.; Lawley, T.J.

1983-01-01

The sera of 21 patients with psoriasis were examined for the presence of IgA-containing circulating immune complexes (CIC) using the Raji IgA radioimmunoassay. In addition, the Raji IgG radioimmunoassay and 125I-Clq binding assay were used to detect IgG- and IgM-containing CIC. Twenty-five patients with other hyperkeratotic skin disorders were studied as controls. Patients were studied before institution of systemic therapy with etretinate (20 patients) or 13-cis-retinoic acid (1 patient). In addition, sera of 15 of the patients treated with etretinate were studied before, during, and after therapy. The extent of pretreatment disease involvement as well as response to therapy were evaluated in a blinded fashion. Fourteen of 21 (67%) patients with psoriasis had evidence of IgA-containing CIC at some time during the course of their disease, as compared to only 1 of 25 patients with other hyperkeratotic skin disorders. In contrast, only 2 of 19 (11%) had evidence of IgG-containing CIC using the Raji IgG assay, and only 1 of 19 (5%) had evidence of IgG- or IgM-containing CIC using the 125I-Clq binding assay. A positive correlation was found between the extent of pretreatment disease involvement and the level of IgA-containing CIC by linear regression analysis (p . 0.01). There was, however, no correlation between clinical improvement and the presence or level of IgA-containing CIC in 15 patients followed during therapy. Sucrose density gradient analysis of the IgA-containing CIC found in 2 of these patients demonstrated IgA-containing CIC in the 9S to 13S region. The finding of IgA-containing CIC in a significant number of patients with psoriasis and the relative absence of IgG- or IgM-containing CIC suggest that IgA-containing CIC may play a role in psoriasis

Characterization of an antigenic site that contains a dominant, type-specific neutralization determinant on the envelope protein domain III (ED3) of dengue 2 virus

International Nuclear Information System (INIS)

Gromowski, Gregory D.; Barrett, Alan D.T.

2007-01-01

The surface of the mature dengue virus (DENV) particle consists of 90 envelope (E) protein dimers that mediate both receptor binding and fusion. The E protein ectodomain can be divided into three structural domains designated ED1, ED2, and ED3, of which ED3 contains the critical and dominant virus-specific neutralization sites. In this study the ED3 epitopes recognized by seven, murine, IgG1 DENV-2 type-specific, monoclonal antibodies (MAbs) were determined using site-directed mutagenesis of a recombinant DENV-2 ED3 (rED3) protein. A total of 41 single amino acid substitutions were introduced into the rED3 at 30 different surface accessible residues. The affinity of each MAb with the mutant rED3s was assessed by indirect ELISA and the results indicate that all seven MAbs recognize overlapping epitopes with residues K305 and P384 critical for binding. These residues are conserved among DENV-2 strains and cluster together on the upper lateral face of ED3. A linear relationship was observed between relative occupancy of ED3 on the virion by MAb and neutralization of the majority of virus infectivity (∼ 90%) for all seven MAbs. Depending on the MAb, it is predicted that between 10% and 50% relative occupancy of ED3 on the virion is necessary for virus neutralization and for all seven MAbs occupancy levels approaching saturation were required for 100% neutralization of virus infectivity. Overall, the conserved antigenic site recognized by all seven MAbs is likely to be a dominant DENV-2 type-specific, neutralization determinant

Receptor-binding domain of SARS-CoV spike protein induces highly potent neutralizing antibodies: implication for developing subunit vaccine

International Nuclear Information System (INIS)

He Yuxian; Zhou Yusen; Liu Shuwen; Kou Zhihua; Li Wenhui; Farzan, Michael; Jiang Shibo

2004-01-01

The spike (S) protein of severe acute respiratory syndrome (SARS) coronavirus (CoV), a type I transmembrane envelope glycoprotein, consists of S1 and S2 domains responsible for virus binding and fusion, respectively. The S1 contains a receptor-binding domain (RBD) that can specifically bind to angiotensin-converting enzyme 2 (ACE2), the receptor on target cells. Here we show that a recombinant fusion protein (designated RBD-Fc) containing 193-amino acid RBD (residues 318-510) and a human IgG1 Fc fragment can induce highly potent antibody responses in the immunized rabbits. The antibodies recognized RBD on S1 domain and completely inhibited SARS-CoV infection at a serum dilution of 1:10,240. Rabbit antisera effectively blocked binding of S1, which contains RBD, to ACE2. This suggests that RBD can induce highly potent neutralizing antibody responses and has potential to be developed as an effective and safe subunit vaccine for prevention of SARS

A peptide extension dictates IgM assembly.

Science.gov (United States)

Pasalic, Dzana; Weber, Benedikt; Giannone, Chiara; Anelli, Tiziana; Müller, Roger; Fagioli, Claudio; Felkl, Manuel; John, Christine; Mossuto, Maria Francesca; Becker, Christian F W; Sitia, Roberto; Buchner, Johannes

2017-10-10

Professional secretory cells can produce large amounts of high-quality complex molecules, including IgM antibodies. Owing to their multivalency, polymeric IgM antibodies provide an efficient first-line of defense against pathogens. To decipher the mechanisms of IgM assembly, we investigated its biosynthesis in living cells and faithfully reconstituted the underlying processes in vitro. We find that a conserved peptide extension at the C-terminal end of the IgM heavy (Ig-μ) chains, termed the tailpiece, is necessary and sufficient to establish the correct geometry. Alanine scanning revealed that hydrophobic amino acids in the first half of the tailpiece contain essential information for generating the correct topology. Assembly is triggered by the formation of a disulfide bond linking two tailpieces. This induces conformational changes in the tailpiece and the adjacent domain, which drive further polymerization. Thus, the biogenesis of large and topologically challenging IgM complexes is dictated by a local conformational switch in a peptide extension.

Fc-Glycosylation in Human IgG1 and IgG3 Is Similar for Both Total and Anti-Red-Blood Cell Anti-K Antibodies

Directory of Open Access Journals (Sweden)

Myrthe E. Sonneveld

2018-01-01

Full Text Available After albumin, immunoglobulin G (IgG are the most abundant proteins in human serum, with IgG1 and IgG3 being the most abundant subclasses directed against protein antigens. The quality of the IgG-Fc-glycosylation has important functional consequences, which have been found to be skewed toward low fucosylation in some antigen-specific immune responses. This increases the affinity to IgG1-Fc-receptor (FcγRIIIa/b and thereby directly affects downstream effector functions and disease severity. To date, antigen-specific IgG-glycosylation have not been analyzed for IgG3. Here, we analyzed 30 pregnant women with anti-K alloantibodies from a prospective screening cohort and compared the type of Fc-tail glycosylation of total serum- and antigen-specific IgG1 and IgG3 using mass spectrometry. Total serum IgG1 and IgG3 Fc-glycoprofiles were highly similar. Fc glycosylation of antigen-specific IgG varied greatly between individuals, but correlated significantly with each other for IgG1 and IgG3, except for bisection. However, although the magnitude of changes in fucosylation and galactosylation were similar for both subclasses, this was not the case for sialylation levels, which were significantly higher for both total and anti-K IgG3. We found that the combination of relative IgG1 and IgG3 Fc-glycosylation levels did not improve the prediction of anti-K mediated disease over IgG1 alone. In conclusion, Fc-glycosylation profiles of serum- and antigen-specific IgG1 and IgG3 are highly similar.

Comparing domain interactions within antibody Fabs with kappa and lambda light chains.

Science.gov (United States)

Toughiri, Raheleh; Wu, Xiufeng; Ruiz, Diana; Huang, Flora; Crissman, John W; Dickey, Mark; Froning, Karen; Conner, Elaine M; Cujec, Thomas P; Demarest, Stephen J

2016-10-01

IgG antibodies are multi-domain proteins with complex inter-domain interactions. Human IgG heavy chains (HCs) associate with light chains (LCs) of the κ or λ isotype to form mature antibodies capable of binding antigen. The HC/LC interaction involves 4 domains: VH and CH1 from the HC and VL and CL from the LC. Human Fabs with κ LCs have been well characterized for their unfolding behaviors and demonstrate a significant level of cooperativity and stabilization when all 4 domains are intact. Very little is known regarding the thermodynamic properties of human Fabs with λ LCs. Here, we dissect the domain contributions to Fab stability for both κ and λ LC-containing Fabs. We find the cooperativity of unfolding between the constant domains, CH1/Cλ, and variable domains, VH/Vλ, within λ LC-containing Fabs is significantly weaker than that of κ LC-containing Fabs. The data suggests there may not be an evolutionary necessity for strong variable/constant domain cooperativity within λ LC-containing Fabs. After investigating the biophysical properties of Fabs with mismatched variable and constant domain subunits (e.g., VH/Vκ paired with CH1/Cλ or T cell receptor Cα/Cβ), the major role of the constant domains for both κ- and λ-containing Fabs may be to reduce the hydrophobic exposure at the VH/VL interface. Even though Fabs with these non-native pairings were thermodynamically less stable, they secreted well from mammalian cells as well behaved monodisperse proteins, which was in contrast to what was observed with the VH/Vκ and VH/Vλ scFvs that secreted as a mixture of monomer and aggregates.

No association between the protein tyrosine phosphatase, receptor-type, Z Polypeptide 1 (PTPRZ1) gene and schizophrenia in the Japanese population.

Science.gov (United States)

Ito, Yoshihito; Yamada, Shinnosuke; Takahashi, Nagahide; Saito, Shinichi; Yoshimi, Akira; Inada, Toshiya; Noda, Yukihiro; Ozaki, Norio

2008-10-05

NRG1-ERBB signaling influences the risk for schizophrenia pathology. A recent study has reported that MAGI1, MAGI2, and protein tyrosine phosphatase, receptor-type, Z polypeptide 1 (PTPRZ1; located on 7q31.3) gene products regulate the NRG1-ERBB4 signaling pathway, and PTPRZ1 is associated with schizophrenia in a Caucasian population. By applying a gene-based association concept, we analyzed any association between PTPRZ1 tagging SNPs and schizophrenia in the Japanese population (576 schizophrenics and 768 controls). After linkage disequilibrium analysis, 29 single nucleotide polymorphisms (SNPs) were genotyped using a 5'-exonuclease allelic discrimination assay. We found a significant association of one tagging SNP in a genotype-wise analysis (P = 0.007); however, this might be resulted from type I error due to multiple testing (P = 0.17 after SNPSpD correction). No association was observed between schizophrenic patients and controls in either allelic, genotypic, or haplotypic analyses. Our results therefore suggest that PTPRZ1 is unlikely to be related to the development of schizophrenia in the Japanese population.

Different Binding Properties and Function of CXXC Zinc Finger Domains in Dnmt1 and Tet1

Science.gov (United States)

Meilinger, Daniela; Bultmann, Sebastian; Fellinger, Karin; Hasenöder, Stefan; Wang, Mengxi; Qin, Weihua; Söding, Johannes; Spada, Fabio; Leonhardt, Heinrich

2011-01-01

Several mammalian proteins involved in chromatin and DNA modification contain CXXC zinc finger domains. We compared the structure and function of the CXXC domains in the DNA methyltransferase Dnmt1 and the methylcytosine dioxygenase Tet1. Sequence alignment showed that both CXXC domains have a very similar framework but differ in the central tip region. Based on the known structure of a similar MLL1 domain we developed homology models and designed expression constructs for the isolated CXXC domains of Dnmt1 and Tet1 accordingly. We show that the CXXC domain of Tet1 has no DNA binding activity and is dispensable for catalytic activity in vivo. In contrast, the CXXC domain of Dnmt1 selectively binds DNA substrates containing unmethylated CpG sites. Surprisingly, a Dnmt1 mutant construct lacking the CXXC domain formed covalent complexes with cytosine bases both in vitro and in vivo and rescued DNA methylation patterns in dnmt1−/− embryonic stem cells (ESCs) just as efficiently as wild type Dnmt1. Interestingly, neither wild type nor ΔCXXC Dnmt1 re-methylated imprinted CpG sites of the H19a promoter in dnmt1−/− ESCs, arguing against a role of the CXXC domain in restraining Dnmt1 methyltransferase activity on unmethylated CpG sites. PMID:21311766

Different binding properties and function of CXXC zinc finger domains in Dnmt1 and Tet1.

Directory of Open Access Journals (Sweden)

Carina Frauer

2011-02-01

Full Text Available Several mammalian proteins involved in chromatin and DNA modification contain CXXC zinc finger domains. We compared the structure and function of the CXXC domains in the DNA methyltransferase Dnmt1 and the methylcytosine dioxygenase Tet1. Sequence alignment showed that both CXXC domains have a very similar framework but differ in the central tip region. Based on the known structure of a similar MLL1 domain we developed homology models and designed expression constructs for the isolated CXXC domains of Dnmt1 and Tet1 accordingly. We show that the CXXC domain of Tet1 has no DNA binding activity and is dispensable for catalytic activity in vivo. In contrast, the CXXC domain of Dnmt1 selectively binds DNA substrates containing unmethylated CpG sites. Surprisingly, a Dnmt1 mutant construct lacking the CXXC domain formed covalent complexes with cytosine bases both in vitro and in vivo and rescued DNA methylation patterns in dnmt1⁻/⁻ embryonic stem cells (ESCs just as efficiently as wild type Dnmt1. Interestingly, neither wild type nor ΔCXXC Dnmt1 re-methylated imprinted CpG sites of the H19a promoter in dnmt1⁻/⁻ ESCs, arguing against a role of the CXXC domain in restraining Dnmt1 methyltransferase activity on unmethylated CpG sites.

Purification, crystallization and preliminary X-ray analysis of the IgV domain of human nectin-4

OpenAIRE

Xu, Xiang; Zhang, Xiaoai; Lu, Guangwen; Cai, Yongping

2012-01-01

Nectin-4 belongs to a family of immunoglobulin-like cell adhesion molecules and is highly expressed in cancer cells. Recently, nectin-4 was found to be a receptor of measles virus and the IgV domain sustains strong binding to measles virus H protein. In this study, the successful expression and purification of human nectin-4 V domain (nectin-4v) is reported

Establishment of a novel high-affinity IgE receptor-positive canine mast cell line with wild-type c-kit receptors

International Nuclear Information System (INIS)

Amagai, Yosuke; Tanaka, Akane; Ohmori, Keitaro; Matsuda, Hiroshi

2008-01-01

Much is known regarding participations of mast cells with innate and acquired immunity by secreting various cytokines and chemical mediators. However, details of mast cell biology still remain unclear. In this study, we successfully established a novel growth factor-independent mast cell line (MPT-1) derived from canine mast cell tumor. MPT-1 cells manifested factor-independent proliferation as floating cells containing a large amount of histamine, as well as chymase-like dog mast cell protease 3, in cytosolic granules. Particularly, MPT-1 cells expressed high-affinity IgE receptors (FcεRI) and wild-type c-kit receptors. Degranulation of MPT-1 cells was induced not only by stimulation with calcium ionophore but also by cross-linkage of the surface IgE. Given that MPT-1 is the first mast cell line with FcεRI which has no c-kit mutations, MPT-1 cells may provide great contribution for investigation of IgE-mediated activation mechanisms of mast cells, leading to development of effective treatment for allergic disorders

Therapeutic potential of combined anti-IL-1β IgY and anti-TNF-α IgY in guinea pigs with allergic rhinitis induced by ovalbumin.

Science.gov (United States)

Guo-Zhu, Hu; Xi-Ling, Zhu; Zhu, Wen; Li-Hua, Wu; Dan, He; Xiao-Mu, Wu; Wen-Yun, Zhou; Wei-Xu, Hu

2015-03-01

We have previously demonstrated that anti-IL-1β immunoglobulin yolk(IgY) inhibits pathological responses in allergic asthma guinea pigs induced by ovalbumin(OVA). This study aims to determine whether the combined blockade of IL-1β and TNF-α can more effectively inhibit allergic inflammation in allergic rhinitis(AR) guinea pigs induced by OVA. Healthy guinea pigs treated with saline were used as the healthy control. The AR guinea pigs induced by OVA were randomly divided into (1) the AR model group containing negative control animals treated with intranasal saline; (2) the 0.1% non-specific IgY treatment group treated with non-specific IgY; (3) the 0.1% anti-TNF-α IgY treatment group treated with 0.1% anti-TNF-α IgY; (4) the 0.1% anti-IL-1β IgY treatment group treated with 0.1% anti-IL-1β IgY; (5) the 0.1% combined anti-IL-1β IgY and anti-TNF-α IgY treatment group treated with 0.1% combined anti-IL-1β IgY and anti-TNF-α IgY; and (6) the fluticasone propionate treatment group treated with fluticasone propionate. Cytokines were measured using an enzyme-linked immunosorbent assay. The results showed that IL-1β, IL-5, IL-9, IL-13, IL-18, IL-22, IL-33, TNF-α, TGF-β1 and OVA-specific IgE levels in the peripheral blood (PB) and nasal lavage fluid (NLF) significantly decreased at 2h, 4h or 8h in the 0.1% combined anti-IL-1β IgY and anti-TNF-α IgY treatment group compared to the AR model group and the 0.1% non-specific IgY treatment group (P<0.05). The data suggest that blockade of IL-1β and TNF-α by intranasal instillation of combined anti-IL-1β IgY and anti-TNF-α IgY could be a potential alternative strategy for preventing and treating allergic rhinitis. Copyright © 2014. Published by Elsevier B.V.

Histopathology of IgG4-Related Autoimmune Hepatitis and IgG4-Related Hepatopathy in IgG4-Related Disease.

Science.gov (United States)

Nakanuma, Yasuni; Ishizu, Yoji; Zen, Yoh; Harada, Kenichi; Umemura, Takeji

2016-08-01

Immunoglobulin G4-related disease (IgG4-RD) is a systemic disease involving many organs; it includes IgG4-related sclerosing cholangitis and inflammatory pseudotumor in the hepatobiliary system. Two types of hepatic parenchymal involvement have been reported in IgG4-RD: IgG4-related autoimmune hepatitis (AIH) and IgG4-hepatopathy. Moreover, only three cases of IgG4-related AIH have been reported. Immunoglobulin G4-related AIH is clinicopathologically similar to AIH, except for an elevated serum IgG4 level and heavy infiltration of IgG4-positive plasma cells in the liver tissue. Interestingly, IgG4-related AIH can be complicated by well-known IgG4-RD(s). Immunoglobulin G4-hepatopathy, which includes various histopathological lesions encountered in the liver of patients with type I autoimmune pancreatitis, is classified into five histological categories: portal inflammation, large bile duct damage, portal sclerosis, lobular hepatitis, and cholestasis. Immunoglobulin G4-hepatopathy is currently a collective term covering hepatic lesions primarily or secondarily related to IgG4-related sclerosing cholangitis and type 1 autoimmune pancreatitis. In conclusion, the liver is not immune to IgG4-RD, and at least two types of hepatic involvement in IgG4-RD have been reported: IgG4-related AIH and IgG4-hepatopathy. Additional studies are required to clarify their precise clinical significance with respect to IgG4-RD and inherent liver diseases. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

IgE and allergen-specific immunotherapy-induced IgG4 recognize similar epitopes of Bet v 1, the major allergen of birch pollen.

Science.gov (United States)

Groh, N; von Loetzen, C S; Subbarayal, B; Möbs, C; Vogel, L; Hoffmann, A; Fötisch, K; Koutsouridou, A; Randow, S; Völker, E; Seutter von Loetzen, A; Rösch, P; Vieths, S; Pfützner, W; Bohle, B; Schiller, D

2017-05-01

Allergen-specific immunotherapy (AIT) with birch pollen generates Bet v 1-specific immunoglobulin (Ig)G 4 which blocks IgE-mediated hypersensitivity mechanisms. Whether IgG 4 specific for Bet v 1a competes with IgE for identical epitopes or whether novel epitope specificities of IgG 4 antibodies are developed is under debate. We sought to analyze the epitope specificities of IgE and IgG 4 antibodies from sera of patients who received AIT. 15 sera of patients (13/15 received AIT) with Bet v 1a-specific IgE and IgG 4 were analyzed. The structural arrangements of recombinant (r)Bet v 1a and rBet v 1a _11x , modified in five potential epitopes, were analyzed by circular dichroism and nuclear magnetic resonance spectroscopy. IgE binding to Bet v 1 was assessed by ELISA and mediator release assays. Competitive binding of monoclonal antibodies specific for Bet v 1a and serum IgE/IgG 4 to rBet v 1a and serum antibody binding to a non-allergenic Bet v 1-type model protein presenting an individual epitope for IgE was analyzed in ELISA and western blot. rBet v 1a _11x had a Bet v 1a - similar secondary and tertiary structure. Monomeric dispersion of rBet v 1a _11x was concentration and buffer-dependent. Up to 1500-fold increase in the EC 50 for IgE-mediated mediator release induced by rBet v 1a _11x was determined. The reduction of IgE and IgG 4 binding to rBet v 1a _11x was comparable in 67% (10/15) of sera. Bet v 1a-specific monoclonal antibodies inhibited binding of serum IgE and IgG 4 to 66.1% and 64.9%, respectively. Serum IgE and IgG 4 bound specifically to an individual epitope presented by our model protein in 33% (5/15) of sera. Patients receiving AIT develop Bet v 1a-specific IgG 4 which competes with IgE for partly identical or largely overlapping epitopes. The similarities of epitopes for IgE and IgG 4 might stimulate the development of epitope-specific diagnostics and therapeutics. © 2016 John Wiley & Sons Ltd.

The effects of confining pressure on the strength and elastic properties of the Paintbrush tuff recovered from boreholes USW NRG-6 and USW NRG-7/7A: Data report

International Nuclear Information System (INIS)

Martin, R.J.; Noel, J.S.; Boyd, P.J.

1997-09-01

Experimental results are presented for bulk and mechanical properties measurements on specimens of the Paintbrush tuff recovered from the USW NRG-6 and USW NRG-7/7A borehole at Yucca Mountain, Nevada. Measurements have been performed on five thermal/mechanical units: TCw, PTn, TSw2, and TSw3. The following bulk properties are reported for each specimen: dry bulk density, saturated bulk density, average grain density and porosity. Confined compression to failure tests were performed on selected specimens recovered from the boreholes at confining pressures of 5 and 10 MPa. In addition, compressional and shear wave velocities were measured on the specimens prior to testing. Measurements were conducted under drained conditions at room temperature on nominally water saturated specimens. The nominal strain rate for the experiments was 10 -5 s -1

IgD in the reptile leopard gecko.

Science.gov (United States)

Gambón-Deza, Francisco; Espinel, Christian Sánchez

2008-07-01

Immunoglobulin D (IgD) has been a mysterious antibody ever since it was discovered in mammals 40 years ago. It shares with IgM the role of antigen-receptor in the membrane of mature B cells. The absence of IgD in birds and its description in bony fishes contributed to the confusion about its evolutionary origins. Recent studies have established the presence of IgD in the amphibian Xenopus tropicalis. It is essential to study IgD genes in reptiles in order to better understand the evolution of this immunoglobulin in vertebrates. We describe in this report the IgM and IgD genes of the reptile Eublepharis macularius. The IgM gene has characteristics that are similar to those described in other species whereas IgD gene departs from the normal structure described for this antibody class in other species. It is made up of 11 immunoglobulins domains without evidence of recent intragenic duplications of exons as described in IgD genes of fish and X.tropicalis. It is possible that the immunoglobulin is comprised of domains inherited from earlier species and that this form of IgD is close to that present in animals that left the sea to live on land. Furthermore, domains CH7 and CH8 of E. macularius IgD are orthologues to domains CH2 and CH3 of mammalian IgD. The present study also describes a second IgD (IgD2) which must have appeared recently by duplication of an older immunoglobulin gene and recombination with the IgA-like gene described in this specie. Tissue expression of IgD and IgD2 mRNA is similar to that of IgM mRNA, suggesting a functional role of reptilian IgD.

Report of the collaboration project for research and development of sphere-pac fuel among JNC-PSI-NRG (1). Planning, fuel design, pin fabrication

International Nuclear Information System (INIS)

Morihira, Masayuki; Ozawa, Takayuki; Tomita, Yutaka; Suzuki, Masahiro; Kihara, Yoshiyuki; Shigetome, Yoshiaki; Kohno, Shusaku

2004-07-01

The collaboration project concerning sphere-pac fuel among JNC, Swiss PSI (Paul Scherrer Institut) and Dutch NRG (Nuclear Research and Consultancy Group) is in progress. Final target of the project is comparative irradiation tests of sphere-pac fuel in the HFR (High Flux Reactor) in Petten in the Netherlands with pellet type fuel and vipack fuel. Total 16 fuel segments (8 pins) of these three types of fuel are planned to be irradiated. Two sphere-pac fuel segments contain 5%Np in addition to 20%Pu-MOX. Other segments contain no Np. The objective of the irradiation tests is to obtain the restructuring data in the early beginning of life for SPF as well as power-to-melt test data for the potential study of SPF. At the same time introduction of modeling technique for irradiation performance analysis, fuel design, fuel fabrication is also important objective for JNC. Fabrication of irradiation test pins was completed till May 2003 in PSI. After transportation of the fuel pins to Petten, two times of irradiation were performed in January to March in 2004 and now post irradiation tests are in progress. Later two irradiations will be done till the autumn in 2004. This report summarized the basic plan, fuel design, and fabrication of irradiation test pins concerning this collaboration project. (author)

The PD-1/PD-L1 complex resembles the antigen-binding Fv domains of antibodies and T cell receptors

Energy Technology Data Exchange (ETDEWEB)

Lin, David Yin-wei; Tanaka, Yoshimasa; Iwasaki, Masashi; Gittis, Apostolos G.; Su, Hua-Poo; Mikami, Bunzo; Okazaki, Taku; Honjo, Tasuku; Minato, Nagahiro; Garboczi, David N. (NIH); (Kyoto)

2008-07-29

Signaling through the programmed death 1 (PD-1) inhibitory receptor upon binding its ligand, PD-L1, suppresses immune responses against autoantigens and tumors and plays an important role in the maintenance of peripheral immune tolerance. Release from PD-1 inhibitory signaling revives 'exhausted' virus-specific T cells in chronic viral infections. Here we present the crystal structure of murine PD-1 in complex with human PD-L1. PD-1 and PD-L1 interact through the conserved front and side of their Ig variable (IgV) domains, as do the IgV domains of antibodies and T cell receptors. This places the loops at the ends of the IgV domains on the same side of the PD-1/PD-L1 complex, forming a surface that is similar to the antigen-binding surface of antibodies and T cell receptors. Mapping conserved residues allowed the identification of residues that are important in forming the PD-1/PD-L1 interface. Based on the structure, we show that some reported loss-of-binding mutations involve the PD-1/PD-L1 interaction but that others compromise protein folding. The PD-1/PD-L1 interaction described here may be blocked by antibodies or by designed small-molecule drugs to lower inhibitory signaling that results in a stronger immune response. The immune receptor-like loops offer a new surface for further study and potentially the design of molecules that would affect PD-1/PD-L1 complex formation and thereby modulate the immune response.

Long-term human immune system reconstitution in non-obese diabetic (NOD)-Rag (-)-γ chain (-) (NRG) mice is similar but not identical to the original stem cell donor.

Science.gov (United States)

Harris, D T; Badowski, M; Balamurugan, A; Yang, O O

2013-12-01

The murine immune system is not necessarily identical to it human counterpart, which has led to the construction of humanized mice. The current study analysed whether or not a human immune system contained within the non-obese diabetic (NOD)-Rag1(null) -γ chain(null) (NRG) mouse model was an accurate representation of the original stem cell donor and if multiple mice constructed from the same donor were similar to one another. To that end, lightly irradiated NRG mice were injected intrahepatically on day 1 of life with purified cord blood-derived CD34(+) stem and progenitor cells. Multiple mice were constructed from each cord blood donor. Mice were analysed quarterly for changes in the immune system, and followed for periods up to 12 months post-transplant. Mice from the same donor were compared directly with each other as well as with the original donor. Analyses were performed for immune reconstitution, including flow cytometry, T cell receptor (TCR) and B cell receptor (BCR) spectratyping. It was observed that NRG mice could be 'humanized' long-term using cord blood stem cells, and that animals constructed from the same cord blood donor were nearly identical to one another, but quite different from the original stem cell donor immune system. © 2013 British Society for Immunology.

Hierarchical, domain type-specific acquisition of antibodies to Plasmodium falciparum erythrocyte membrane protein 1 in Tanzanian children

DEFF Research Database (Denmark)

Cham, Gerald K K; Turner, Louise; Kurtis, Jonathan D

2010-01-01

Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is a variant antigen expressed on the surface of malaria-infected erythrocytes. PfEMP1 attaches to the vascular lining and allows infected erythrocytes to avoid filtration through the spleen. Each parasite genome encodes about 60 diffe...... and play a major role in limiting parasite multiplication in the blood.......Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is a variant antigen expressed on the surface of malaria-infected erythrocytes. PfEMP1 attaches to the vascular lining and allows infected erythrocytes to avoid filtration through the spleen. Each parasite genome encodes about 60...... different PfEMP1 variants, each PfEMP1 comprises several domains in its extracellular region, and the PfEMP1 repertoire in different parasites contains domain types that are serologically cross-reactive. In this longitudinal study, we followed 672 children living in an area of high malaria transmission...

Geotechnical characterization of the North Ramp of the Exploratory Studies Facility: Yucca Mountain Site Characterization Project. Volume 2, NRG corehole data appendices

International Nuclear Information System (INIS)

Brechtel, C.E.; Lin, Ming; Martin, E.; Kessel, D.S.

1995-05-01

This report presents the results of the geological and geotechnical characterization of the Miocene volcanic tuff rocks of the Timber Mountain and Paintbrush groups that the tunnel boring machine will encounter during excavations of the Exploratory Studies Facility (ESF) North Ramp. The information in this report was developed to support the design of the ESF North Ramp. The ESF is being constructed by the DOE as part of the Yucca Mountain Project site characterization activities. The purpose of these activities is to evaluate the potential to locate the national high-level nuclear waste repository on land within and adjacent to the Nevada Test Site (NTS), Nye County, Nevada. This report was prepared as part of the Soil and Rock Properties Studies in accordance with the 8.3.1.14.2 Study Plan to Provide Soil and Rock Properties. This is volume 2 which contains NRG Corehole Data for each of the NRG Holes

Geotechnical characterization of the North Ramp of the Exploratory Studies Facility: Yucca Mountain Site Characterization Project. Volume 2, NRG corehole data appendices

Energy Technology Data Exchange (ETDEWEB)

Brechtel, C.E.; Lin, Ming; Martin, E. [Agapito Associates, Inc., Grand Junction, CO (United States); Kessel, D.S. [Sandia National Labs., Albuquerque, NM (United States)

1995-05-01

This report presents the results of the geological and geotechnical characterization of the Miocene volcanic tuff rocks of the Timber Mountain and Paintbrush groups that the tunnel boring machine will encounter during excavations of the Exploratory Studies Facility (ESF) North Ramp. The information in this report was developed to support the design of the ESF North Ramp. The ESF is being constructed by the DOE as part of the Yucca Mountain Project site characterization activities. The purpose of these activities is to evaluate the potential to locate the national high-level nuclear waste repository on land within and adjacent to the Nevada Test Site (NTS), Nye County, Nevada. This report was prepared as part of the Soil and Rock Properties Studies in accordance with the 8.3.1.14.2 Study Plan to Provide Soil and Rock Properties. This is volume 2 which contains NRG Corehole Data for each of the NRG Holes.

Molecular determinants for the complex binding specificity of the PDZ domain in PICK1

DEFF Research Database (Denmark)

Madsen, Kenneth L; Beuming, Thijs; Niv, Masha Y

2005-01-01

PICK1 (protein interacting with C kinase 1) contains a single PDZ domain known to mediate interaction with the C termini of several receptors, transporters, ion channels, and kinases. In contrast to most PDZ domains, the PICK1 PDZ domain interacts with binding sequences classifiable as type I (te...

The human 64-kDa polyadenylylation factor contains a ribonucleoprotein-type RNA binding domain and unusual auxiliary motifs

International Nuclear Information System (INIS)

Takagaki, Yoshio; Manley, J.L.; MacDonald, C.C.; Shenk, T.

1992-01-01

Cleavage stimulation factor is one of the multiple factors required for 3'-end cleavage of mammalian pre-mRNAs. The authors have shown previously that this factor is composed of three subunits with estimated molecular masses of 77, 64, and 50 kDa and that the 64-kDa subunit can be UV-cross linked to RNA in a polyadenylylation signal (AAUAAA)-dependent manner. They have now isolated cDNAs encoding the 64-kDa subunit of human cleavage stimulation factor. The 64-kDa subunit contains a ribonucleoprotein-type RNA binding domain in the N-terminal region and a repeat structure in the C-terminal region in which a pentapeptide sequence (consensus MEARA/G) is repeated 12 times and the formation of a long α-helix stabilized by salt bridges is predicted. An ∼270-amino acid segment surrounding this repeat structure is highly enriched in proline and glycine residues (∼20% for each). When cloned 64-kDa subunit was expressed in Escherichia coli, an N-terminal fragment containing the RNA binding domain bound to RNAs in a polyadenylylation-signal-independent manner, suggesting that the RNA binding domain is directly involved in the binding of the 64-kDa subunit to pre-mRNAs

Elimination of soluble 123I-labeled aggregates of IgG in patients with systemic lupus erythematosus. Effect of serum IgG and numbers of erythrocyte complement receptor type 1

International Nuclear Information System (INIS)

Halma, C.; Breedveld, F.C.; Daha, M.R.; Blok, D.; Evers-Schouten, J.H.; Hermans, J.; Pauwels, E.K.; van Es, L.A.

1991-01-01

Using soluble 123 I-labeled aggregates of human IgG ( 123 I-AHIgG) as a probe, we examined the function of the mononuclear phagocyte system in 22 patients with systemic lupus erythematosus (SLE) and 12 healthy controls. In SLE patients, a decreased number of erythrocyte complement receptor type 1 was associated with less binding of 123 I-AHIgG to erythrocytes and a faster initial rate of elimination of 123 I-AHIgG (mean +/- SEM half-maximal clearance time 5.23 +/- 0.2 minutes, versus 6.58 +/- 0.2 minutes in the controls), with possible spillover of the material outside the mononuclear phagocyte system of the liver and spleen. However, multiple regression analysis showed that serum concentrations of IgG were the most important factor predicting the rate of 123 I-AHIgG elimination. IgG concentration may thus reflect immune complex clearance, which in turn, would influence the inflammatory reaction, in SLE

A novel soluble immune-type receptor (SITR in teleost fish: carp SITR is involved in the nitric oxide-mediated response to a protozoan parasite.

Directory of Open Access Journals (Sweden)

Carla M S Ribeiro

2011-01-01

Full Text Available The innate immune system relies upon a wide range of germ-line encoded receptors including a large number of immunoglobulin superfamily (IgSF receptors. Different Ig-like immune receptor families have been reported in mammals, birds, amphibians and fish. Most innate immune receptors of the IgSF are type I transmembrane proteins containing one or more extracellular Ig-like domains and their regulation of effector functions is mediated intracellularly by distinct stimulatory or inhibitory pathways.Carp SITR was found in a substracted cDNA repertoire from carp macrophages, enriched for genes up-regulated in response to the protozoan parasite Trypanoplasma borreli. Carp SITR is a type I protein with two extracellular Ig domains in a unique organisation of a N-proximal V/C2 (or I- type and a C-proximal V-type Ig domain, devoid of a transmembrane domain or any intracytoplasmic signalling motif. The carp SITR C-proximal V-type Ig domain, in particular, has a close sequence similarity and conserved structural characteristics to the mammalian CD300 molecules. By generating an anti-SITR antibody we could show that SITR protein expression was restricted to cells of the myeloid lineage. Carp SITR is abundantly expressed in macrophages and is secreted upon in vitro stimulation with the protozoan parasite T. borreli. Secretion of SITR protein during in vivo T. borreli infection suggests a role for this IgSF receptor in the host response to this protozoan parasite. Overexpression of carp SITR in mouse macrophages and knock-down of SITR protein expression in carp macrophages, using morpholino antisense technology, provided evidence for the involvement of carp SITR in the parasite-induced NO production.We report the structural and functional characterization of a novel soluble immune-type receptor (SITR in a teleost fish and propose a role for carp SITR in the NO-mediated response to a protozoan parasite.

Avaliação das subclasses IgG1 e IgG3 na doença hemolítica perinatal Assessment of IgG1 and IgG3 subclasses in perinatal hemolytic disease

Directory of Open Access Journals (Sweden)

Maria A. Araújo

2003-01-01

Full Text Available A doença hemolítica perinatal (DHPN ainda é um problema clínico. Nenhum teste isolado prediz, com segurança, a gravidade do quadro hemolítico. O objetivo do presente estudo foi determinar as subclasses de anticorpos IgG1 e IgG3 por citometria de fluxo no soro de 42 gestantes isoimunizadas e correlacionar os dados obtidos com a gravidade da DHPN. A distribuição dos fetos ou neonatos segundo a gravidade do quadro hemolítico evidenciou 13 casos com doença leve, 16 casos com doença moderada e 13 com doença grave. As subclasses foram detectadas em 33/42 (79% amostras. A subclasse IgG1, isoladamente, foi evidenciada em 14/33 (42,4% casos. Na relação entre gravidade da doença e subclasses de IgG, observou-se que IgG1 isolada foi encontrada em todos os grupos, e os valores da mediana de intensidade de fluorescência (MIF foram significativamente mais altos nas formas mais graves da DHPN (pThe hemolytic disease of the newborn (HDN continues to be a clinical problem in spite of prophylaxis. To date, none of the available tests, developed to predict the severity of HDN, has provided complete reliability. The objective of the present study was to determine the IgG1 and IgG3 subclasses in 42 isoimmunized pregnant women, and to correlate them with clinical severity of hemolytic disease. The IgG subclasses were determined employing flow cytometry. According to the clinical severity of HDN, fetuses and newborn babies were classified as 13 mild, 16 moderate and 13 severe cases. The IgG subclasses were detected in 33 of the 42 pregnant women. Of these, IgG1 was predominant in 72.7% of the cases; either isolated (42.4% or in association with IgG3 (30.3%. IgG1 was present in all the three clinical severity categories, however, its values were significantly higher in cases with greater clinical severity of HDN (p<0.01. On the other hand, the distribution of IgG3 values within each group was not statistically significant (p=0.11. IgG3 seems to be more

Amino acid sequence requirements in the human IgA1 hinge for cleavage by streptococcal IgA1 proteases

DEFF Research Database (Denmark)

Senior, BW; Batten, MR; Kilian, Mogens

2002-01-01

All the IgA1 proteases of the different pathogenic species of Streptococcus cleave the hinge of the alpha chain of human IgA1 only at one proline-threonine peptide bond. In order to study the importance of these amino acids for cleavage, several hinge mutant recombinant IgA1 antibodies were const...... constructed. The mutations were found to be without major effect upon the structure or functional abilities of the antibodies. However, they had a major effect upon their sensitivity to cleavage by some of the IgA1 proteases....

A Patient with Autoimmune Pancreatitis Type 1 with Previously Known Lymphadenopathy, Both in the Context of IgG4-related Disease.

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Alidjan, Fazil M; Karim, Faiz; Verdijk, Rob M; van Esser, Joost W; van Heerde, Marianne J

2015-11-05

Autoimmune pancreatitis (AIP) is an important clinical pathologic concept of IgG-4-related disease. AIP is a rare cause of chronic pancreatitis, characterized by a fibroinflammatory process by lymphoplasmacytic infiltrates, storiform fibrosis, obliterative phlebitis, and increased IgG4+ plasma cells, leading to dysfunction of the pancreas. Affected patients with AIP frequently have disease affecting other organs or sites with similar histologic changes, elevated IgG4+ plasma cell infiltrate, and good response to corticosteroid therapy. These diseases often are not limited to the pancreas and the pancreas may not be involved at all. We report a 62-year-old man with obstructive jaundice with pre-existent submandibular lymphadenopathy. Diagnosis of AIP was based on diagnostic criteria by the HISORT-criteria in combination with elevated IgG-4 serum levels. CT revealed a focal enlargement of the head of the pancreas, as well as mesenteric peripancreatic and mediastinal lymphadenopathy. He was treated with high-dose steroid in combination with azathioprine and showed good clinical response. We report a case with pre-existent submandibular lymphadenopathy and obstructive jaundice based on AIP type 1, both in the context of IgG4-related disease.

Structural Studies of the SET Domain from RIZ1 Tumor Suppressor

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Briknarova, Klara; Zhou, Xinliang; Satterthwait, Arnold C.; Hoyt, David W.; Ely, Kathryn R.; Huang, Shi

2008-02-15

Histone lysine methyltransferases (HKMTs) are involved in regulation of chromatin structure, and, as such, are important for longterm gene activation and repression that is associated with cell memory and establishment of cell-type specific transcriptional programs. Most HKMTs contain a SET domain, which is responsible for their catalytic activity. RIZ1 is a transcription regulator and tumor suppressor that catalyzes methylation of lysine 9 of histone H3 and contains a rather distinct SET domain. Similar SET domains, sometimes refererred to as PR (PRDI-BF1 and RIZ1 homology) domains, are also found in other proteins including Blimp-1/PRDI-BF1, MDS1-EVI1 and Meisetz. We determined the solution structure of the PR domain from RIZ1 and characterized its interaction with S-adenosyl homocysteine (SAH) and a peptide from histone H3. Despite low sequence identity with canonical SET domains, the PR domain displays a typical SET fold including a pseudo-knot at the C-terminus. The N-flanking sequence of RIZ1 PR domain adopts a novel conformation and interacts closely with the SET fold. The C-flanking sequence contains an α-helix that exhibits higher mobility than the SET fold and points away from the protein face that harbors active site in other SET domains. Residues that interact with the methylation cofactor in SET domains are not conserved in RIZ1 or other PR domains, and the SET fold of RIZ1 does not bind SAH. However, the PR domain of RIZ1 interacts specifically with a synthetic peptide comprising residues 1-20 of histone H3.

Associations between an IgG3 polymorphism in the binding domain for FcRn, transplacental transfer of malaria-specific IgG3, and protection against Plasmodium falciparum malaria during infancy: A birth cohort study in Benin.

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Celia Dechavanne

2017-10-01

Full Text Available Transplacental transfer of maternal immunoglobulin G (IgG to the fetus helps to protect against malaria and other infections in infancy. Recent studies have emphasized the important role of malaria-specific IgG3 in malaria immunity, and its transfer may reduce the risk of malaria in infancy. Human IgGs are actively transferred across the placenta by binding the neonatal Fc receptor (FcRn expressed within the endosomes of the syncytiotrophoblastic membrane. Histidine at position 435 (H435 provides for optimal Fc-IgG binding. In contrast to other IgG subclasses, IgG3 is highly polymorphic and usually contains an arginine at position 435, which reduces its binding affinity to FcRn in vitro. The reduced binding to FcRn is associated with reduced transplacental transfer and reduced half-life of IgG3 in vivo. Some haplotypes of IgG3 have histidine at position 435. This study examines the hypotheses that the IgG3-H435 variant promotes increased transplacental transfer of malaria-specific antibodies and a prolonged IgG3 half-life in infants and that its presence correlates with protection against clinical malaria during infancy.In Benin, 497 mother-infant pairs were included in a longitudinal birth cohort. Both maternal and cord serum samples were assayed for levels of IgG1 and IgG3 specific for MSP119, MSP2 (both allelic families, 3D7 and FC27, MSP3, GLURP (both regions, R0 and R2, and AMA1 antigens of Plasmodium falciparum. Cord:maternal ratios were calculated. The maternal IgG3 gene was sequenced to identify the IgG3-H435 polymorphism. A multivariate logistic regression was used to examine the association between maternal IgG3-H435 polymorphism and transplacental transfer of IgG3, adjusting for hypergammaglobulinemia, maternal malaria, and infant malaria exposure. Twenty-four percent of Beninese women living in an area highly endemic for malaria had the IgG3-H435 allele (377 women homozygous for the IgG3-R435 allele, 117 women heterozygous for the Ig

N=1 domain wall solutions of massive type II supergravity as generalized geometries

International Nuclear Information System (INIS)

Louis, J.

2006-05-01

We study N=1 domain wall solutions of type IIB supergravity compactified on a Calabi-Yau manifold in the presence of RR and NS electric and magnetic fluxes. We show that the dynamics of the scalar fields along the direction transverse to the domain wall is described by gradient flow equations controlled by a superpotential W. We then provide a geometrical interpretation of the gradient flow equations in terms of the mirror symmetric compactification of type IIA. They correspond to a set of generalized Hitchin flow equations of a manifold with SU(3) x SU(3)structure which is fibered over the direction transverse to the domain wall. (Orig.)

Regulation of abiotic stress signalling by Arabidopsis C-terminal domain phosphatase-like 1 requires interaction with a k-homology domain-containing protein.

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In Sil Jeong

Full Text Available Arabidopsis thaliana CARBOXYL-TERMINAL DOMAIN (CTD PHOSPHATASE-LIKE 1 (CPL1 regulates plant transcriptional responses to diverse stress signals. Unlike typical CTD phosphatases, CPL1 contains two double-stranded (ds RNA binding motifs (dsRBMs at its C-terminus. Some dsRBMs can bind to dsRNA and/or other proteins, but the function of the CPL1 dsRBMs has remained obscure. Here, we report identification of REGULATOR OF CBF GENE EXPRESSION 3 (RCF3 as a CPL1-interacting protein. RCF3 co-purified with tandem-affinity-tagged CPL1 from cultured Arabidopsis cells and contains multiple K-homology (KH domains, which were predicted to be important for binding to single-stranded DNA/RNA. Yeast two-hybrid, luciferase complementation imaging, and bimolecular fluorescence complementation analyses established that CPL1 and RCF3 strongly associate in vivo, an interaction mediated by the dsRBM1 of CPL1 and the KH3/KH4 domains of RCF3. Mapping of functional regions of CPL1 indicated that CPL1 in vivo function requires the dsRBM1, catalytic activity, and nuclear targeting of CPL1. Gene expression profiles of rcf3 and cpl1 mutants were similar during iron deficiency, but were distinct during the cold response. These results suggest that tethering CPL1 to RCF3 via dsRBM1 is part of the mechanism that confers specificity to CPL1-mediated transcriptional regulation.

Structure of the C-terminal heme-binding domain of THAP domain containing protein 4 from Homo sapiens

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Bianchetti, Christopher M.; Bingman, Craig A.; Phillips, Jr., George N. (UW)

2012-03-15

The thanatos (the Greek god of death)-associated protein (THAP) domain is a sequence-specific DNA-binding domain that contains a C2-CH (Cys-Xaa{sub 2-4}-Cys-Xaa{sub 35-50}-Cys-Xaa{sub 2}-His) zinc finger that is similar to the DNA domain of the P element transposase from Drosophila. THAP-containing proteins have been observed in the proteome of humans, pigs, cows, chickens, zebrafish, Drosophila, C. elegans, and Xenopus. To date, there are no known THAP domain proteins in plants, yeast, or bacteria. There are 12 identified human THAP domain-containing proteins (THAP0-11). In all human THAP protein, the THAP domain is located at the N-terminus and is {approx}90 residues in length. Although all of the human THAP-containing proteins have a homologous N-terminus, there is extensive variation in both the predicted structure and length of the remaining protein. Even though the exact function of these THAP proteins is not well defined, there is evidence that they play a role in cell proliferation, apoptosis, cell cycle modulation, chromatin modification, and transcriptional regulation. THAP-containing proteins have also been implicated in a number of human disease states including heart disease, neurological defects, and several types of cancers. Human THAP4 is a 577-residue protein of unknown function that is proposed to bind DNA in a sequence-specific manner similar to THAP1 and has been found to be upregulated in response to heat shock. THAP4 is expressed in a relatively uniform manner in a broad range of tissues and appears to be upregulated in lymphoma cells and highly expressed in heart cells. The C-terminal domain of THAP4 (residues 415-577), designated here as cTHAP4, is evolutionarily conserved and is observed in all known THAP4 orthologs. Several single-domain proteins lacking a THAP domain are found in plants and bacteria and show significant levels of homology to cTHAP4. It appears that cTHAP4 belongs to a large class of proteins that have yet to be fully

Activation of MAPK overrides the termination of myelin growth and replaces Nrg1/ErbB3 signals during Schwann cell development and myelination

NARCIS (Netherlands)

M.E. Sheean (Maria); E. McShane (Erik); C. Cheret (Cyril); J. Walcher (Jan); T. Müller (Thomas); A. Wulf-Goldenberg (Annika); S. Hoelper (Soraya); A.N. Garratt (Alistair); M. Krüger (Markus); K. Rajewsky (Klaus); D.N. Meijer (Dies); W. Birchmeier (Walter); G.R. Lewin (Gary); M. Selbach (Matthias); C. Birchmeier (Carmen)

2014-01-01

textabstractMyelination depends on the synthesis of large amounts of myelin transcripts and proteins and is controlled by Nrg1/ErbB/Shp2 signaling. We developed a novel pulse labeling strategy based on stable isotope labeling with amino acids in cell culture (SILAC) to measure the dynamics of myelin

Analysis of a two-domain binding site for the urokinase-type plasminogen activator-plasminogen activator inhibitor-1 complex in low-density-lipoprotein-receptor-related protein.

Science.gov (United States)

Andersen, O M; Petersen, H H; Jacobsen, C; Moestrup, S K; Etzerodt, M; Andreasen, P A; Thøgersen, H C

2001-07-01

The low-density-lipoprotein-receptor (LDLR)-related protein (LRP) is composed of several classes of domains, including complement-type repeats (CR), which occur in clusters that contain binding sites for a multitude of different ligands. Each approximately 40-residue CR domain contains three conserved disulphide linkages and an octahedral Ca(2+) cage. LRP is a scavenging receptor for ligands from extracellular fluids, e.g. alpha(2)-macroglobulin (alpha(2)M)-proteinase complexes, lipoprotein-containing particles and serine proteinase-inhibitor complexes, like the complex between urokinase-type plasminogen activator (uPA) and the plasminogen activator inhibitor-1 (PAI-1). In the present study we analysed the interaction of the uPA-PAI-1 complex with an ensemble of fragments representing a complete overlapping set of two-domain fragments accounting for the ligand-binding cluster II (CR3-CR10) of LRP. By ligand blotting, solid-state competition analysis and surface-plasmon-resonance analysis, we demonstrate binding to multiple CR domains, but show a preferential interaction between the uPA-PAI-1 complex and a two-domain fragment comprising CR domains 5 and 6 of LRP. We demonstrate that surface-exposed aspartic acid and tryptophan residues at identical positions in the two homologous domains, CR5 and CR6 (Asp(958,CR5), Asp(999,CR6), Trp(953,CR5) and Trp(994,CR6)), are critical for the binding of the complex as well as for the binding of the receptor-associated protein (RAP) - the folding chaperone/escort protein required for transport of LRP to the cell surface. Accordingly, the present work provides (1) an identification of a preferred binding site within LRP CR cluster II; (2) evidence that the uPA-PAI-1 binding site involves residues from two adjacent protein domains; and (3) direct evidence identifying specific residues as important for the binding of uPA-PAI-1 as well as for the binding of RAP.

Identification of the NC1 domain of {alpha}3 chain as critical for {alpha}3{alpha}4{alpha}5 type IV collagen network assembly.

Science.gov (United States)

LeBleu, Valerie; Sund, Malin; Sugimoto, Hikaru; Birrane, Gabriel; Kanasaki, Keizo; Finan, Elizabeth; Miller, Caroline A; Gattone, Vincent H; McLaughlin, Heather; Shield, Charles F; Kalluri, Raghu

2010-12-31

The network organization of type IV collagen consisting of α3, α4, and α5 chains in the glomerular basement membrane (GBM) is speculated to involve interactions of the triple helical and NC1 domain of individual α-chains, but in vivo evidence is lacking. To specifically address the contribution of the NC1 domain in the GBM collagen network organization, we generated a mouse with specific loss of α3NC1 domain while keeping the triple helical α3 chain intact by connecting it to the human α5NC1 domain. The absence of α3NC1 domain leads to the complete loss of the α4 chain. The α3 collagenous domain is incapable of incorporating the α5 chain, resulting in the impaired organization of the α3α4α5 chain-containing network. Although the α5 chain can assemble with the α1, α2, and α6 chains, such assembly is incapable of functionally replacing the α3α4α5 protomer. This novel approach to explore the assembly type IV collagen in vivo offers novel insights in the specific role of the NC1 domain in the assembly and function of GBM during health and disease.

EH domain of EHD1

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Kieken, Fabien; Jovic, Marko; Naslavsky, Naava; Caplan, Steve, E-mail: scaplan@unmc.edu; Sorgen, Paul L. [University of Nebraska Medical Center, Department of Biochemistry and Molecular Biology and Eppley Cancer Center (United States)], E-mail: psorgen@unmc.edu

2007-12-15

EHD1 is a member of the mammalian C-terminal Eps15 homology domain (EH) containing protein family, and regulates the recycling of various receptors from the endocytic recycling compartment to the plasma membrane. The EH domain of EHD1 binds to proteins containing either an Asn-Pro-Phe or Asp-Pro-Phe motif, and plays an important role in the subcellular localization and function of EHD1. Thus far, the structures of five N-terminal EH domains from other proteins have been solved, but to date, the structure of the EH domains from the four C-terminal EHD family paralogs remains unknown. In this study, we have assigned the 133 C-terminal residues of EHD1, which includes the EH domain, and solved its solution structure. While the overall structure resembles that of the second of the three N-terminal Eps15 EH domains, potentially significant differences in surface charge and the structure of the tripeptide-binding pocket are discussed.

EH domain of EHD1

International Nuclear Information System (INIS)

Kieken, Fabien; Jovic, Marko; Naslavsky, Naava; Caplan, Steve; Sorgen, Paul L.

2007-01-01

EHD1 is a member of the mammalian C-terminal Eps15 homology domain (EH) containing protein family, and regulates the recycling of various receptors from the endocytic recycling compartment to the plasma membrane. The EH domain of EHD1 binds to proteins containing either an Asn-Pro-Phe or Asp-Pro-Phe motif, and plays an important role in the subcellular localization and function of EHD1. Thus far, the structures of five N-terminal EH domains from other proteins have been solved, but to date, the structure of the EH domains from the four C-terminal EHD family paralogs remains unknown. In this study, we have assigned the 133 C-terminal residues of EHD1, which includes the EH domain, and solved its solution structure. While the overall structure resembles that of the second of the three N-terminal Eps15 EH domains, potentially significant differences in surface charge and the structure of the tripeptide-binding pocket are discussed

A monoclonal antibody distinguishes between two IgM heavy chain isotypes in Atlantic salmon and brown trout: protein characterization, 3D modeling and epitope mapping.

Science.gov (United States)

Kamil, Atif; Falk, Knut; Sharma, Animesh; Raae, Arnt; Berven, Frode; Koppang, Erling Olaf; Hordvik, Ivar

2011-09-01

Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) possess two distinct subpopulations of IgM which can be separated by anion exchange chromatography. Accordingly, there are two isotypic μ genes in these species, related to ancestral tetraploidy. In the present work it was verified by mass spectrometry that IgM of peak 1 (subpopulation 1) have heavy chains previously designated as μB type whereas IgM of peak 2 (subpopulation 2) have heavy chains of μA type. Two adjacent cysteine residues are present near the C-terminal part of μB, in contrast to one cysteine residue in μA. Salmon IgM of both peak 1 and peak 2 contain light chains of the two most common isotypes: IgL1 and IgL3. In contrast to salmon and brown trout, IgM of rainbow trout (Oncorhynchus mykiss) is eluted in a single peak when subjected to anion exchange chromatography. Surprisingly, a monoclonal antibody MAb4C10 against rainbow trout IgM, reacted with μA in salmon, whereas in brown trout it reacted with μB. It is plausible to assume that DNA has been exchanged between the paralogous A and B loci during evolution while maintaining the two sub-variants, with and without the extra cysteine. MAb4C10 was conjugated to magnetic beads and used to separate cells, demonstrating that μ transcripts residing from captured cells were primarily of A type in salmon and B type in brown trout. An analysis of amino acid substitutions in μA and μB of salmon and brown trout indicated that the third constant domain is essential for MAb4C10 binding. This was supported by 3D modeling and was finally verified by studies of MAb4C10 reactivity with a series of recombinant μ3 constructs. Copyright © 2011 Elsevier Ltd. All rights reserved.

The first structure in a family of peptidase inhibitors reveals an unusual Ig-like fold [v2; ref status: indexed, http://f1000r.es/1nx

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Daniel J Rigden

2013-08-01

Full Text Available We report the crystal structure solution of the Intracellular Protease Inhibitor (IPI protein from Bacillus subtilis, which has been reported to be an inhibitor of the intracellular subtilisin Isp1 from the same organism. The structure of IPI is a variant of the all-beta, immunoglobulin (Ig fold. It is possible that IPI is important for protein-protein interactions, of which inhibition of Isp1 is one. The intracellular nature of ISP is questioned, because an alternative ATG codon in the ipi gene would produce a protein with an N-terminal extension containing a signal peptide. It is possible that alternative initiation exists, producing either an intracellular inhibitor or a secreted form that may be associated with the cell surface.  Homologues of the IPI protein from other species are multi-domain proteins, containing signal peptides and domains also associated with the bacterial cell-surface. The cysteine peptidase inhibitors chagasin and amoebiasin also have Ig-like folds, but their topology differs significantly from that of IPI, and they share no recent common ancestor. A model of IPI docked to Isp1 shows similarities to other subtilisin:inhibitor complexes, particularly where the inhibitor interacts with the peptidase active site.

HIV-1-Specific IgA Monoclonal Antibodies from an HIV-1 Vaccinee Mediate Galactosylceramide Blocking and Phagocytosis

Science.gov (United States)

2018-01-01

ABSTRACT Vaccine-elicited humoral immune responses comprise an array of antibody forms and specificities, with only a fraction contributing to protective host immunity. Elucidation of antibody effector functions responsible for protective immunity against human immunodeficiency virus type 1 (HIV-1) acquisition is a major goal for the HIV-1 vaccine field. Immunoglobulin A (IgA) is an important part of the host defense against pathogens; however, little is known about the role of vaccine-elicited IgA and its capacity to mediate antiviral functions. To identify the antiviral functions of HIV-1-specific IgA elicited by vaccination, we cloned HIV-1 envelope-specific IgA monoclonal antibodies (MAbs) by memory B cell cultures from peripheral blood mononuclear cells from an RV144 vaccinee and produced two IgA clonal cell lines (HG129 and HG130) producing native, nonrecombinant IgA MAbs. The HG129 and HG130 MAbs mediated phagocytosis by monocytes, and HG129 blocked HIV-1 Env glycoprotein binding to galactosylceramide, an alternative HIV-1 receptor. These findings elucidate potential antiviral functions of vaccine-elicited HIV-1 envelope-specific IgA that may act to block HIV-1 acquisition at the portal of entry by preventing HIV-1 binding to galactosylceramide and mediating antibody Fc receptor-mediated virion phagocytosis. Furthermore, these findings highlight the complex and diverse interactions of vaccine-elicited IgA with pathogens that depend on IgA fine specificity and form (e.g., multimeric or monomeric) in the systemic circulation and mucosal compartments. IMPORTANCE Host-pathogen interactions in vivo involve numerous immune mechanisms that can lead to pathogen clearance. Understanding the nature of antiviral immune mechanisms can inform the design of efficacious HIV-1 vaccine strategies. Evidence suggests that both neutralizing and nonneutralizing antibodies can mediate some protection against HIV in animal models. Although numerous studies have characterized the

The carcinoembryonic antigen IgV-like N domain plays a critical role in the implantation of metastatic tumor cells.

Science.gov (United States)

Abdul-Wahid, Aws; Huang, Eric H-B; Cydzik, Marzena; Bolewska-Pedyczak, Eleonora; Gariépy, Jean

2014-03-01

The human carcinoembryonic antigen (CEA) is a cell adhesion molecule involved in both homotypic and heterotypic interactions. The aberrant overexpression of CEA on adenocarcinoma cells correlates with their increased metastatic potential. Yet, the mechanism(s) by which its adhesive properties can lead to the implantation of circulating tumor cells and expansion of metastatic foci remains to be established. In this study, we demonstrate that the IgV-like N terminal domain of CEA directly participates in the implantation of cancer cells through its homotypic and heterotypic binding properties. Specifically, we determined that the recombinant N terminal domain of CEA directly binds to fibronectin (Fn) with a dissociation constant in the nanomolar range (K(D) 16 ± 3 nM) and interacts with itself (K(D) 100 ± 17 nM) and more tightly to the IgC-like A(3) domain (K(D) 18 ± 3 nM). Disruption of these molecular associations through the addition of antibodies specific to the CEA N or A(3)B(3) domains, or by adding soluble recombinant forms of the CEA N, A(3) or A(3)B(3) domains or a peptide corresponding to residues 108-115 of CEA resulted in the inhibition of CEA-mediated intercellular aggregation and adherence events in vitro. Finally, pretreating CEA-expressing murine colonic carcinoma cells (MC38.CEA) with rCEA N, A3 or A(3)B(3) modules blocked their implantation and the establishment of tumor foci in vivo. Together, these results suggest a new mechanistic insight into how the CEA IgV-like N domain participates in cellular events that can have a macroscopic impact in terms of cancer progression and metastasis. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Peptides Derived from Type IV Collagen, CXC Chemokines, and Thrombospondin-1 Domain-Containing Proteins Inhibit Neovascularization and Suppress Tumor Growth in MDA-MB-231 Breast Cancer Xenografts

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Jacob E. Koskimaki

2009-12-01

Full Text Available Angiogenesis or neovascularization, the process of new blood vessel formation from preexisting microvasculature, involves interactions among several cell types including parenchymal, endothelial cells, and immune cells. The formation of new vessels is tightly regulated by a balance between endogenous proangiogenic and antiangiogenic factors to maintain homeostasis in tissue; tumor progression and metastasis in breast cancer have been shown to be angiogenesis-dependent. We previously introduced a systematic methodology to identify putative endogenous antiangiogenic peptides and validated these predictions in vitro in human umbilical vein endothelial cell proliferation and migration assays. These peptides are derived from several protein families including type IV collagen, CXC chemokines, and thrombospondin-1 domain-containing proteins. On the basis of the results from the in vitro screening, we have evaluated the ability of one peptide selected from each family named pentastatin-1, chemokinostatin-1, and properdistatin, respectively, to suppress angiogenesis in an MDA-MB-231 human breast cancer orthotopic xenograft model in severe combined immunodeficient mice. Peptides were administered intraperitoneally once per day. We have demonstrated significant suppression of tumor growth in vivo and subsequent reductions in microvascular density, indicating the potential of these peptides as therapeutic agents for breast cancer.

Elevated factor H-related protein 1 and factor H pathogenic variants decrease complement regulation in IgA nephropathy.

Science.gov (United States)

Tortajada, Agustín; Gutiérrez, Eduardo; Goicoechea de Jorge, Elena; Anter, Jaouad; Segarra, Alfons; Espinosa, Mario; Blasco, Miquel; Roman, Elena; Marco, Helena; Quintana, Luis F; Gutiérrez, Josué; Pinto, Sheila; Lopez-Trascasa, Margarita; Praga, Manuel; Rodriguez de Córdoba, Santiago

2017-10-01

IgA nephropathy (IgAN), a frequent cause of chronic kidney disease worldwide, is characterized by mesangial deposition of galactose-deficient IgA1-containing immune complexes. Complement involvement in IgAN pathogenesis is suggested by the glomerular deposition of complement components and the strong protection from IgAN development conferred by the deletion of the CFHR3 and CFHR1 genes (Δ CFHR3-CFHR1 ). Here we searched for correlations between clinical progression and levels of factor H (FH) and FH-related protein 1 (FHR-1) using well-characterized patient cohorts consisting of 112 patients with IgAN, 46 with non-complement-related autosomal dominant polycystic kidney disease (ADPKD), and 76 control individuals. Patients with either IgAN or ADPKD presented normal FH but abnormally elevated FHR-1 levels and FHR-1/FH ratios compared to control individuals. Highest FHR-1 levels and FHR-1/FH ratios are found in patients with IgAN with disease progression and in patients with ADPKD who have reached chronic kidney disease, suggesting that renal function impairment elevates the FHR-1/FH ratio, which may increase FHR-1/FH competition for activated C3 fragments. Interestingly, Δ CFHR3-CFHR1 homozygotes are protected from IgAN, but not from ADPKD, and we found five IgAN patients with low FH carrying CFH or CFI pathogenic variants. These data support a decreased FH activity in IgAN due to increased FHR-1/FH competition or pathogenic CFH variants. They also suggest that alternative pathway complement activation in patients with IgAN, initially triggered by galactose-deficient IgA1-containing immune complexes, may exacerbate in a vicious circle as renal function deterioration increase FHR-1 levels. Thus, a role of FHR-1 in IgAN pathogenesis is to compete with complement regulation by FH. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Ganglioside-specific IgG and IgA recruit leukocyte effector functions in Guillain-Barre syndrome

NARCIS (Netherlands)

Sorge, N.M. van; Yuki, N.; Koga, M.; Susuki, K.; Jansen, M.D.; Kooten, C. van; Wokke, J.H.; Winkel, J.G.J. van de; Pol, W.L. van der; Berg, L.H. van den

2007-01-01

The capacity of ganglioside-specific autoantibodies to recruit leukocyte effector functions was studied. Serum samples from 87 patients with Guillain–Barré (GBS) or Miller Fisher syndrome (MFS), containing GM1-, GQ1b-, or GD1b-specific IgG or IgA, were tested for leukocyte activating capacity.

Structure of a mouse immunoglobulin G that lacks the entire CH1 domain: Protein sequencing and small-angle X-ray scattering studies

International Nuclear Information System (INIS)

Igarashi, Takako; Tanaka, Toshiyuki; Nakanishi, Mamoru; Arata, Yoji; Sato, Mamoru; Katsube, Yukiteru; Takio, Koji

1990-01-01

The structure of a short-chain IgG2a antibody, which is a member of the family of mouse anti-dansyl switch variant antibodies with identical variable regions but different heavy-chain constant regions, is reported. Amino acid sequencing analyses have demonstrated that in the short-chain IgG2a antibody the entire C H 1 domain is deleted whereas the hinge region remains intact. Small-angle X-ray scattering data were collected for the short-chain IgG2a antibody and compared with those for the switch variant IgG1, IgG2a, and IgG2b antibodies with the normal heavy chain. It has been concluded that deletion of the C H 1 domain results in a large structural change and the short-chain IgG2a antibody possesses an elongated molecular shape with a much smaller hinge angle as compared with the normal IgG2a antibody that is a Y-shaped molecule

Structural requirements for cub domain containing protein 1 (CDCP1 and Src dependent cell transformation.

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Gwendlyn Kollmorgen

Full Text Available Cub domain containing protein 1 (CDCP1 is strongly expressed in tumors derived from lung, colon, ovary, or kidney. It is a membrane protein that is phosphorylated and then bound by Src family kinases. Although expression and phosphorylation of CDCP1 have been investigated in many tumor cell lines, the CDCP1 features responsible for transformation have not been fully evaluated. This is in part due to the lack of an experimental system in which cellular transformation depends on expression of exogenous CDCP1 and Src. Here we use retrovirus mediated co-overexpression of c-Src and CDCP1 to induce focus formation of NIH3T3 cells. Employing different mutants of CDCP1 we show that for a full transformation capacity, the intact amino- and carboxy-termini of CDCP1 are essential. Mutation of any of the core intracellular tyrosine residues (Y734, Y743, or Y762 abolished transformation, and mutation of a palmitoylation motif (C689,690G strongly reduced it. Src kinase binding to CDCP1 was not required since Src with a defective SH2 domain generated even more CDCP1 dependent foci whereas Src myristoylation was necessary. Taken together, the focus formation assay allowed us to define structural requirements of CDCP1/Src dependent transformation and to characterize the interaction of CDCP1 and Src.

Engineered Lactobacillus rhamnosus GG expressing IgG-binding domains of protein G: Capture of hyperimmune bovine colostrum antibodies and protection against diarrhea in a mouse pup rotavirus infection model.

Science.gov (United States)

Günaydın, Gökçe; Zhang, Ran; Hammarström, Lennart; Marcotte, Harold

2014-01-16

Rotavirus-induced diarrhea causes more than 500,000 deaths annually in the world, and although vaccines are being made available, new effective treatment strategies should still be considered. Purified antibodies derived from hyperimmune bovine colostrum (HBC), from cows immunized with rotavirus, were previously used for treatment of rotavirus diarrhea in children. A combination of HBC antibodies and a probiotic strain of Lactobacillus (L. rhamnosus GG) was also found to be more effective than HBC alone in reducing diarrhea in a mouse model of rotavirus infection. In order to further improve this form of treatment, L. rhamnosus GG was engineered to display surface expressed IgG-binding domains of protein G (GB1, GB2, and GB3) which capture HBC-derived IgG antibodies (HBC-IgG) and thus target rotavirus. The expression of IgG-binding domains on the surface of the bacteria as well as their binding to HBC-IgG and to rotavirus (simian strain RRV) was demonstrated by Western blot, flow cytometry, and electron microscopy. The prophylactic effect of engineered L. rhamnosus GG and anti-rotaviral activity of HBC antibodies was evaluated in a mouse pup model of RRV infection. The combination therapy with engineered L. rhamnosus GG (PG3) and HBC was significantly more effective in reducing the prevalence, severity, and duration of diarrhea in comparison to HBC alone or a combination of wild-type L. rhamnosus GG and HBC. The new therapy reduces the effective dose of HBC between 10 to 100-fold and may thus decrease treatment costs. This antibody capturing platform, tested here for the first time in vivo, could potentially be used to target additional gastrointestinal pathogens. Copyright © 2013 Elsevier Ltd. All rights reserved.

Structure of an isolated unglycosylated antibody CH2 domain

International Nuclear Information System (INIS)

Prabakaran, Ponraj; Vu, Bang K.; Gan, Jianhua; Feng, Yang; Dimitrov, Dimiter S.; Ji, Xinhua

2008-01-01

The crystal structure of an isolated unglycosylated antibody C H 2 domain has been determined at 1.7 Å resolution. The C H 2 (C H 3 for IgM and IgE) domain of an antibody plays an important role in mediating effector functions and preserving antibody stability. It is the only domain in human immunoglobulins (Igs) which is involved in weak interchain protein–protein interactions with another C H 2 domain solely through sugar moieties. The N-linked glycosylation at Asn297 is conserved in mammalian IgGs as well as in homologous regions of other antibody isotypes. To examine the structural details of the C H 2 domain in the absence of glycosylation and other antibody domains, the crystal structure of an isolated unglycosylated antibody γ1 C H 2 domain was determined at 1.7 Å resolution and compared with corresponding C H 2 structures from intact Fc, IgG and Fc receptor complexes. Furthermore, the oligomeric state of the protein in solution was studied using size-exclusion chromatography. The results suggested that the unglycosylated human antibody C H 2 domain is a monomer and that its structure is similar to that found in the intact Fc, IgG and Fc receptor complex structures. However, certain structural variations were observed in the Fc receptor-binding sites. Owing to its small size, stability and non-immunogenic Ig template, the C H 2-domain structure could be useful for the development by protein design of antibody domains exerting effector functions and/or antigen specificity and as a robust scaffold in protein-engineering applications

Radioimmunoassay of IgM, IgG, and IgA brucella antibodies

International Nuclear Information System (INIS)

Parrett, D.; Nielson, K.H.; White, R.G.; Payne, D.J.H.

1977-01-01

A radioimmunoassay (R.I.A.) has been devised to measure the serum antibody against Brucella abortus in each of the immunoglobulin classes IgM, IgG, and IgA. This test was applied to 46 sera from individuals with various clinical types of brucellosis, and the results were compared with the results of conventional direct and indirect agglutination and complement-fixation tests. The R.I.A. provided a highly sensitive primary-type assay which avoided the difficulties with blocking or non-agglutinating antibody, and thus has many advantages in the diagnosis of acute and chronic stages of brucella infection in man. The R.I.A. was successful in detection of antibody in many instances in which conventional serological tests were negative, and such antibody could (if IgM) be associated with acute or (if IgG or IgA) with chronic cases of brucellosis. One case in which B.abortus was isolated by blood culture but which failed to yield antibody by conventional tests, nevertheless showed substantial levels of IgM and IgG antibody by R.I.A. In other cases the R.I.A. test helped to eliminate the diagnosis of brucellosis by revealing absent or low antibody levels. (author)

Effect of Dialkyl Ammonium Cationic Surfactants on the Microfluidity of Membranes Containing Raft Domains.

Science.gov (United States)

Uyama, Makoto; Inoue, Kaori; Kinoshita, Koichi; Miyahara, Reiji; Yokoyama, Hirokazu; Nakano, Minoru

2018-01-01

It has been reported that a lot of receptors localize in lipid raft domains and that the microfluidity of these domains regulates the activation of these receptors. In this study, we focused on the lipid raft and in order to evaluate the physicochemical effects of surfactants on microfluidity of lipid membranes, we used liposomes comprising of egg-yolk L-α-phosphatidylcholine, egg-yolk sphingomyelin, and cholesterol as a model of cell membranes containing raft domains. The microfluidity of the domains was characterized by fluorescence spectrometry using 1,6-diphenyl-1,3,5-hexatriene and 2-dimethylamino-6-lauroylnaphthalene. Among several surfactants, dialkylammonium-type cationic surfactants most efficiently increased the microfluidity. It is therefore concluded that (1) the electrostatic interaction between the cationic surfactant and eggPC/eggSM/cholesterol liposome could be important, (2) surfactants with alkyl chains more effectively inserted into membranes than those with acyl chains, and (3) cationic surfactants with lower T m values have a greater ability to increase the fluidity.

IgG4-related disease

DEFF Research Database (Denmark)

Detlefsen, Sönke; Klöppel, Günter

2018-01-01

disease (IgG4-RD). The histologic key findings are lymphoplasmacytic infiltration rich in IgG4-positive plasma cells combined with storiform fibrosis and obliterative phlebitis. Among the organs mainly affected by IgG4-RD are the pancreas and the extrahepatic bile ducts. The pancreatic and biliary...... alterations have been described under the terms autoimmune pancreatitis (AIP) and sclerosing cholangitis, respectively. These diseases are currently more precisely called IgG4-related pancreatitis (or type 1 AIP to distinguish it from type 2 AIP that is unrelated to IgG4-RD) and IgG4-related sclerosing...... cholangitis (IgG4-related SC). Clinically and grossly, both diseases commonly imitate pancreatic and biliary adenocarcinoma, tumors that are well known for their dismal prognosis. As IgG4-RD responds to steroid treatment, making a resection of a suspected tumor unnecessary, a biopsy is often required...

The C-terminal extension of human RTEL1, mutated in Hoyeraal-Hreidarsson syndrome, contains harmonin-N-like domains.

Science.gov (United States)

Faure, Guilhem; Revy, Patrick; Schertzer, Michael; Londono-Vallejo, Arturo; Callebaut, Isabelle

2014-06-01

Several studies have recently shown that germline mutations in RTEL1, an essential DNA helicase involved in telomere regulation and DNA repair, cause Hoyeraal-Hreidarsson syndrome (HHS), a severe form of dyskeratosis congenita. Using original new softwares, facilitating the delineation of the different domains of the protein and the identification of remote relationships for orphan domains, we outline here that the C-terminal extension of RTEL1, downstream of its catalytic domain and including several HHS-associated mutations, contains a yet unidentified tandem of harmonin-N-like domains, which may serve as a hub for partner interaction. This finding highlights the potential critical role of this region for the function of RTEL1 and gives insights into the impact that the identified mutations would have on the structure and function of these domains. © 2013 Wiley Periodicals, Inc.

Human milk containing specific secretory IgA inhibits binding of Giardia lamblia to nylon and glass surfaces.

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Samra, H K; Ganguly, N K; Mahajan, R C

1991-06-01

The effects of human milk, containing specific secretory IgA, on the adherence of Giardia lamblia trophozoites in the presence and in the absence of intestinal mucus in vitro were studied. It was found that the trophozoites treated with breast milk, containing specific secretory IgA to G. lamblia, showed a significant decrease (p less than 0.01) in adherence to nylon fibre columns and glass surfaces than did trophozoites treated with milk containing no SIgA antibodies. The adherence to glass surfaces was significantly more (p less than 0.01) in the presence of intestinal mucus than when the mucus was absent. Milk that did not contain specific secretory SIgA to G. lamblia did not decrease the adherence to glass surfaces either in the presence or in the absence of mucus. The fluorescence study revealed the binding of specific secretory IgA on the trophozoite surface. The results suggest that binding of SIgA antibodies in milk to G. lamblia trophozoites inhibits parasite adherence, thus protecting against this infection in breast-fed babies.

DNA methylation in Cosmc promoter region and aberrantly glycosylated IgA1 associated with pediatric IgA nephropathy.

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Qiang Sun

Full Text Available IgA nephropathy (IgAN is one of the most common glomerular diseases leading to end-stage renal failure. Elevation of aberrantly glycosylated IgA1 is a key feature of it. The expression of the specific molecular chaperone of core1ß1, 3galactosyl transferase (Cosmc is known to be reduced in IgAN. We aimed to investigate whether the methylation of CpG islands of Cosmc gene promoter region could act as a possible mechanism responsible for down-regulation of Cosmc and related higher secretion of aberrantly glycosylated IgA1in lymphocytes from children with IgA nephropathy. Three groups were included: IgAN children (n = 26, other renal diseases (n = 11 and healthy children (n = 13. B-lymphocytes were isolated and cultured, treated or not with IL-4 or 5-Aza-2'-deoxycytidine (AZA. The levels of DNA methylation of Cosmc promotor region were not significantly different between the lymphocytes of the three children populations (P = 0.113, but there were significant differences between IgAN lymphocytes and lymphocytes of the other two children populations after IL-4 (P<0.0001 or AZA (P<0.0001. Cosmc mRNA expression was low in IgAN lymphocytes compared to the other two groups (P<0.0001. The level of aberrantly glycosylated IgA1 was markedly higher in IgAN group compared to the other groups (P<0.0001. After treatment with IL-4, the levels of Cosmc DNA methylation and aberrantly glycosylated IgA1 in IgAN lymphocytes were remarkably higher than the other two groups (P<0.0001 with more markedly decreased Cosmc mRNA content (P<0.0001. After treatment with AZA, the levels in IgAN lymphocytes were decreased, but was still remarkably higher than the other two groups (P<0.0001, while Cosmc mRNA content in IgAN lymphocytes were more markedly increased than the other two groups (P<0.0001. The alteration of DNA methylation by IL-4 or AZA specifically correlates in IgAN lymphocytes with alterations in Cosmc mRNA expression and with the level of aberrantly glycosylated

T cell Ig domain and mucin domain 1 engagement on invariant NKT cells in the presence of TCR stimulation enhances IL-4 production but inhibits IFN-gamma production.

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Kim, Hye Sung; Kim, Hyun Soo; Lee, Chang Woo; Chung, Doo Hyun

2010-04-15

The T cell Ig domain and mucin domain (TIM)1 protein expressed on the surface of Th2 cells regulates the immune response by modulating cytokine production. However, the functional roles of TIM1 have not been examined in NKT cells. Therefore, we investigated the immunologic effects of TIM1 on NKT cells. We found that mouse NK1.1(+)TCR-beta(+), alpha-galactosyl ceramide/CD1d dimer(+) NKT, and NKT hybridoma (DN32.D3) cells constitutively express TIM1 and TIM4 on their surface. Engagement of TIM1 on NKT cells by any of several anti-TIM1 mAbs suppressed the production of IFN-gamma in the presence of TCR stimulation in vitro and in vivo, whereas the effects of such engagement on Th2 cytokine production by the NKT cells varied with the particular anti-TIM1 Ab clone. Moreover, in DN32.D3 TIM4-knockdown NKT hybridoma cells, TIM1 engagement by rTIM1 or TIM4 enhanced IL-4 production while inhibiting IFN-gamma production in the presence of alpha-galactosyl ceramide stimulation. TIM1 engagement increased GATA-3 expression but reduced T-bet expression in NKT cells in the presence of TCR engagement. The adoptive transfer of NKT cells preincubated with anti-TIM1 mAbs into Jalpha18(-/-) mice aggravated bleomycin-induced pulmonary fibrosis by suppressing IFN-gamma production. Taken together, these results suggest that TIM1 costimulation on NKT cells enhances the cellular production of IL-4 while inhibiting the production of IFN-gamma. Thus, as a differential regulator of the immune response, TIM1 on NKT cells may be a useful therapeutic target for immune diseases.

Stabilizing the CH2 Domain of an Antibody by Engineering in an Enhanced Aromatic Sequon.

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Chen, Wentao; Kong, Leopold; Connelly, Stephen; Dendle, Julia M; Liu, Yu; Wilson, Ian A; Powers, Evan T; Kelly, Jeffery W

2016-07-15

Monoclonal antibodies (mAbs) exhibiting highly selective binding to a protein target constitute a large and growing proportion of the therapeutics market. Aggregation of mAbs results in the loss of their therapeutic efficacy and can result in deleterious immune responses. The CH2 domain comprising part of the Fc portion of Immunoglobulin G (IgG) is typically the least stable domain in IgG-type antibodies and therefore influences their aggregation propensity. We stabilized the CH2 domain by engineering an enhanced aromatic sequon (EAS) into the N-glycosylated C'E loop and observed a 4.8 °C increase in the melting temperature of the purified IgG1 Fc fragment. This EAS-stabilized CH2 domain also conferred enhanced stability against thermal and low pH induced aggregation in the context of a full-length monoclonal IgG1 antibody. The crystal structure of the EAS-stabilized (Q295F/Y296A) IgG1 Fc fragment confirms the design principle, i.e., the importance of the GlcNAc1•F295 interaction, and surprisingly reveals that the core fucose attached to GlcNAc1 also engages in an interaction with F295. Inhibition of core fucosylation confirms the contribution of the fucose-Phe interaction to the stabilization. The Q295F/Y296A mutations also modulate the binding affinity of the full-length antibody to Fc receptors by decreasing the binding to low affinity Fc gamma receptors (FcγRIIa, FcγRIIIa, and FcγRIIIb), while maintaining wild-type binding affinity to FcRn and FcγRI. Our results demonstrate that engineering an EAS into the N-glycosylated reverse turn on the C'E loop leads to stabilizing N-glycan-protein interactions in antibodies and that this modification modulates antibody-Fc receptor binding.

IgM and IgD B cell receptors differentially respond to endogenous antigens and control B cell fate

Science.gov (United States)

Noviski, Mark; Mueller, James L; Satterthwaite, Anne; Garrett-Sinha, Lee Ann; Brombacher, Frank

2018-01-01

Naive B cells co-express two BCR isotypes, IgM and IgD, with identical antigen-binding domains but distinct constant regions. IgM but not IgD is downregulated on autoreactive B cells. Because these isotypes are presumed to be redundant, it is unknown how this could impose tolerance. We introduced the Nur77-eGFP reporter of BCR signaling into mice that express each BCR isotype alone. Despite signaling strongly in vitro, IgD is less sensitive than IgM to endogenous antigen in vivo and developmental fate decisions are skewed accordingly. IgD-only Lyn−/− B cells cannot generate autoantibodies and short-lived plasma cells (SLPCs) in vivo, a fate thought to be driven by intense BCR signaling induced by endogenous antigens. Similarly, IgD-only B cells generate normal germinal center, but impaired IgG1+ SLPC responses to T-dependent immunization. We propose a role for IgD in maintaining the quiescence of autoreactive B cells and restricting their differentiation into autoantibody secreting cells. PMID:29521626

Type 1 Autoimmune Pancreatitis and IgG4-Related Sclerosing Cholangitis Is Associated With Extrapancreatic Organ Failure, Malignancy, and Mortality in a Prospective UK Cohort

Science.gov (United States)

Kumar, M.; Hurst, J.M.; Rodriguez-Justo, M.; Chapman, M.H.; Johnson, G.J.; Pereira, S.P.; Chapman, R.W.

2015-01-01

OBJECTIVES Type I autoimmune pancreatitis (AIP) and IgG4-related sclerosing cholangitis (IgG4-related SC) are now recognized as components of a multisystem IgG4-related disease (IgG4-RD). We aimed to define the clinical course and long-term outcomes in patients with AIP/IgG4-SC recruited from two large UK tertiary referral centers. METHODS Data were collected from 115 patients identified between 2004 and 2013, and all were followed up prospectively from diagnosis for a median of 33 months (range 1–107), and evaluated for response to therapy, the development of multiorgan involvement, and malignancy. Comparisons were made with national UK statistics. RESULTS Although there was an initial response to steroids in 97%, relapse occurred in 50% of patients. IgG4-SC was an important predictor of relapse (P IgG4-RD, including three hepatopancreaticobiliary cancers. The risk of any cancer at diagnosis or during follow-up when compared with matched national statistics was increased (odds ratio = 2.25, CI = 1.12–3.94, P = 0.02). Organ dysfunction occurred within the pancreas, liver, kidney, lung, and brain. Mortality occurred in 10% of patients during follow-up. The risk of death was increased compared with matched national statistics (odds ratio = 2.07, CI = 1.07–3.55, P = 0.02). CONCLUSIONS Our findings suggest that AIP and IgG4-SC are associated with significant morbidity and mortality owing to extrapancreatic organ failure and malignancy. Detailed clinical evaluation for evidence of organ dysfunction and associated malignancy is required both at first presentation and during long-term follow-up. PMID:25155229

Dynamics evaluation of total IgG, IgG1 and IgG2a in the serum of mice immunized with radioattenuated paracoccidioides brasiliensis yeast cells

International Nuclear Information System (INIS)

Martins, Estefania M.N.; Andrade, Antero S.R.; Reis, Bernardo S.; Goes, Alfredo M.

2007-01-01

Paracoccidioides brasiliensis is the fungus agent of paracoccidioidomycosis, a deep-seated systemic infection of humans. Up to the moment no vaccine has still been reported. The potential of gamma radiation for pathogens attenuation and vaccine development was explored in this work. In our laboratory we developed radioattenuated yeast cells of P. brasiliensis and the aim of the present work was to evaluate the antibody production dynamics in mice immunized with this cells. Were analyzed the IgG antibodies titers as well as the type of response by analyzing the IgG1 and IgG2a antibody pattern in the course of infection. The mice were divided in two groups that were immunized one time and two times respectively. The mice infected with the virulent P. brasiliensis showed a high level of antibody production while the infection with the radioattenuated yeast did not significantly change the antibody level. The level of IgG raised in both immunized groups after the challenge. In the group immunized one time was not observed a significant difference between the levels of both subclasses when compared with the control. After the challenge of the group immunized two times the IgG2a levels increased significantly when analyzed 90 days post challenge. We concluded that a pattern related to the disease control was apparent in the group submitted to two immunizations. The mice had not developed a totally polarized pattern of TH1/TH2 response but a trend to a TH1 response was evident. (author)

Dynamics evaluation of total IgG, IgG1 and IgG2a in the serum of mice immunized with radioattenuated paracoccidioides brasiliensis yeast cells

Energy Technology Data Exchange (ETDEWEB)

Martins, Estefania M.N.; Andrade, Antero S.R. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)]. E-mail: estefaniabio@yahoo.com.br; antero@cdtn.br; Reis, Bernardo S.; Goes, Alfredo M. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Bioquimica e Imunologia]. E-mail: brsgarbi@mono.icb.ufmg.br; goes@mono.icb.ufmg.br

2007-07-01

Paracoccidioides brasiliensis is the fungus agent of paracoccidioidomycosis, a deep-seated systemic infection of humans. Up to the moment no vaccine has still been reported. The potential of gamma radiation for pathogens attenuation and vaccine development was explored in this work. In our laboratory we developed radioattenuated yeast cells of P. brasiliensis and the aim of the present work was to evaluate the antibody production dynamics in mice immunized with this cells. Were analyzed the IgG antibodies titers as well as the type of response by analyzing the IgG1 and IgG2a antibody pattern in the course of infection. The mice were divided in two groups that were immunized one time and two times respectively. The mice infected with the virulent P. brasiliensis showed a high level of antibody production while the infection with the radioattenuated yeast did not significantly change the antibody level. The level of IgG raised in both immunized groups after the challenge. In the group immunized one time was not observed a significant difference between the levels of both subclasses when compared with the control. After the challenge of the group immunized two times the IgG2a levels increased significantly when analyzed 90 days post challenge. We concluded that a pattern related to the disease control was apparent in the group submitted to two immunizations. The mice had not developed a totally polarized pattern of TH1/TH2 response but a trend to a TH1 response was evident. (author)

The medaka novel immune-type receptor (NITR gene clusters reveal an extraordinary degree of divergence in variable domains

Directory of Open Access Journals (Sweden)

Litman Gary W

2008-06-01

Full Text Available Abstract Background Novel immune-type receptor (NITR genes are members of diversified multigene families that are found in bony fish and encode type I transmembrane proteins containing one or two extracellular immunoglobulin (Ig domains. The majority of NITRs can be classified as inhibitory receptors that possess cytoplasmic immunoreceptor tyrosine-based inhibition motifs (ITIMs. A much smaller number of NITRs can be classified as activating receptors by the lack of cytoplasmic ITIMs and presence of a positively charged residue within their transmembrane domain, which permits partnering with an activating adaptor protein. Results Forty-four NITR genes in medaka (Oryzias latipes are located in three gene clusters on chromosomes 10, 18 and 21 and can be organized into 24 families including inhibitory and activating forms. The particularly large dataset acquired in medaka makes direct comparison possible to another complete dataset acquired in zebrafish in which NITRs are localized in two clusters on different chromosomes. The two largest medaka NITR gene clusters share conserved synteny with the two zebrafish NITR gene clusters. Shared synteny between NITRs and CD8A/CD8B is limited but consistent with a potential common ancestry. Conclusion Comprehensive phylogenetic analyses between the complete datasets of NITRs from medaka and zebrafish indicate multiple species-specific expansions of different families of NITRs. The patterns of sequence variation among gene family members are consistent with recent birth-and-death events. Similar effects have been observed with mammalian immunoglobulin (Ig, T cell antigen receptor (TCR and killer cell immunoglobulin-like receptor (KIR genes. NITRs likely diverged along an independent pathway from that of the somatically rearranging antigen binding receptors but have undergone parallel evolution of V family diversity.

Structure of a mouse immunoglobulin G that lacks the entire C sub H 1 domain: Protein sequencing and small-angle X-ray scattering studies

Energy Technology Data Exchange (ETDEWEB)

Igarashi, Takako; Tanaka, Toshiyuki; Nakanishi, Mamoru; Arata, Yoji (Univ. of Tokyo (Japan)); Sato, Mamoru; Katsube, Yukiteru (Osaka Univ. (Japan)); Takio, Koji (Institute of Physical and Chemical Research, Saitama (Japan))

1990-06-19

The structure of a short-chain IgG2a antibody, which is a member of the family of mouse anti-dansyl switch variant antibodies with identical variable regions but different heavy-chain constant regions, is reported. Amino acid sequencing analyses have demonstrated that in the short-chain IgG2a antibody the entire C{sub H}1 domain is deleted whereas the hinge region remains intact. Small-angle X-ray scattering data were collected for the short-chain IgG2a antibody and compared with those for the switch variant IgG1, IgG2a, and IgG2b antibodies with the normal heavy chain. It has been concluded that deletion of the C{sub H}1 domain results in a large structural change and the short-chain IgG2a antibody possesses an elongated molecular shape with a much smaller hinge angle as compared with the normal IgG2a antibody that is a Y-shaped molecule.

76 FR 36910 - Astoria Generating Company, L.P., NRG Power Marketing LLC, Arthur Kill Power LLC, Astoria Gas...

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2011-06-23

... Generating Company, L.P., NRG Power Marketing LLC, Arthur Kill Power LLC, Astoria Gas Turbine Power LLC... Generating Company, L.P., NRG Power Marketing LLC, Arthur Kill Power LLC, Astoria Gas Turbine Power [[Page... subscribed docket(s). For assistance with any FERC Online service, please e-mail [email protected

Neisseria meningitidis Group A IgG1 and IgG2 Subclass Immune Response in African Children Aged 12–23 Months Following Meningococcal Vaccination

Science.gov (United States)

Holme, Daniel; Findlow, Helen; Sow, Samba O.; Idoko, Olubukola T.; Preziosi, Marie-Pierre; Carlone, George; Plikaytis, Brian D.; Borrow, Ray

2015-01-01

Background. A group A meningococcal conjugate vaccine, PsA-TT, was licensed in 2010 and was previously studied in a phase 2 clinical trial to evaluate its safety and immunogenicity in African children 12–23 months of age. Methods. Subjects received either PsA-TT; meningococcal group A, C, W, Y polysaccharide vaccine (PsACWY); or Haemophilus influenzae type b conjugate vaccine (Hib-TT). Forty weeks following primary vaccination, the 3 groups were further randomized to receive either PsA-TT, one-fifth dose of PsACWY, or Hib-TT. Group A–specific immunoglobulin G (IgG) subclass response was characterized using an enzyme-linked immunosorbent assay. Results. The predominant IgG subclass response, regardless of vaccine, was IgG1. One month following primary vaccination, the geometric mean concentrations (GMCs) of IgG1 and IgG2 in the PsA-TT group were 21.73 µg/mL and 6.27 µg/mL, whereas in the PsACWY group the mean GMCs were 2.01 µg/mL and 0.97 µg/mL, respectively (P Group A–specific IgG1 and IgG2 GMCs remained greater in the PsA-TT group than in the PsACWY group 40 weeks following primary vaccination (P vaccines. Conclusions. Vaccination of African children aged 12–24 months with either PsA-TT or PsACWY elicited a predominantly IgG1 response. The IgG1:IgG2 mean ratio decreased following successive vaccination with PsACWY, indicating a shift toward IgG2, suggestive of the T-cell–independent immune response commonly associated with polysaccharide antigens. Clinical Trials Registration. SRCTN78147026. PMID:26553689

Altered glycosylation of complexed native IgG molecules is associated with disease activity of systemic lupus erythematosus.

Science.gov (United States)

Sjöwall, C; Zapf, J; von Löhneysen, S; Magorivska, I; Biermann, M; Janko, C; Winkler, S; Bilyy, R; Schett, G; Herrmann, M; Muñoz, L E

2015-05-01

In addition to the redundancy of the receptors for the Fc portion of immunoglobulins, glycans result in potential ligands for a plethora of lectin receptors found in immune effector cells. Here we analysed the exposure of glycans containing fucosyl residues and the fucosylated tri-mannose N-type core by complexed native IgG in longitudinal serum samples of well-characterized patients with systemic lupus erythematosus. Consecutive serum samples of a cohort of 15 patients with systemic lupus erythematosus during periods of increased disease activity and remission were analysed. All patients fulfilled the 1982 American College of Rheumatology classification criteria. Sera of 15 sex- and age-matched normal healthy blood donors served as controls. The levels and type of glycosylation of complexed random IgG was measured with lectin enzyme-immunosorbent assays. After specifically gathering IgG complexes from sera, biotinylated lectins Aleuria aurantia lectin and Lens culinaris agglutinin were employed to detect IgG-associated fucosyl residues and the fucosylated tri-mannose N-glycan core, respectively. In sandwich-ELISAs, IgG-associated IgM, IgA, C1q, C3c and C-reactive protein (CRP) were detected as candidates for IgG immune complex constituents. We studied associations of the glycan of complexed IgG and disease activity according to the physician's global assessment of disease activity and the systemic lupus erythematosus disease activity index 2000 documented at the moment of blood taking. Our results showed significantly higher levels of Aleuria aurantia lectin and Lens culinaris agglutinin binding sites exposed on IgG complexes of patients with systemic lupus erythematosus than on those of normal healthy blood donors. Disease activity in systemic lupus erythematosus correlated with higher exposure of Aleuria aurantia lectin-reactive fucosyl residues by immobilized IgG complexes. Top levels of Aleuria aurantia lectin-reactivity were found in samples taken during the

76 FR 34692 - Astoria Generating Company, L.P., NRG Power Marketing LLC, Arthur Kill Power LLC, Astoria Gas...

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2011-06-14

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Identification of the peptide derived from S1 domain that inhibits type I and type II feline infectious peritonitis virus infection.

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Doki, Tomoyoshi; Takano, Tomomi; Koyama, Yusuke; Hohdatsu, Tsutomu

2015-06-02

Feline infectious peritonitis virus (FIPV) can cause a lethal disease in cats, feline infectious peritonitis (FIP). A therapeutic drug that is effective against FIP has not yet been developed. Peptides based on viral protein amino acid sequences have recently been attracting attention as new antiviral drugs. In the present study, we synthesized 30 overlapping peptides based on the amino acid sequence of the S1 domain of the type I FIPV strain KU-2 S protein, and investigated their inhibitory effects on FIPV infection. To evaluate the inhibitory effects on type I FIPV infection of these peptides, we investigated a method to increase the infection efficiency of poorly replicative type I FIPV. The efficiency of type I FIPV infection was increased by diluting the virus with medium containing a polycation. Of the 30 peptides, I-S1-8 (S461-S480), I-S1-9 (S471-S490), I-S1-10 (S481-S500), I-S1-16 (S541-S560), and I-S1-22 (S601-S620) significantly decreased the infectivity of FIPV strain KU-2 while I-S1-9 and I-S1-16 exhibited marked inhibitory effects on FIPV infection. The inhibitory effects on FIPV infection of these 2 peptides on other type I and type II FIPV strains, feline herpesvirus (FHV), and feline calicivirus (FCV) were also examined. These 2 peptides specifically inhibited type I and type II FIPV, but did FHV or FCV infection. In conclusion, the possibility of peptides derived from the S protein of type I FIPV strain KU-2 as anti-FIPV agents effective not only for type I, but also type II FIPV was demonstrated in vitro. Copyright © 2015 Elsevier B.V. All rights reserved.

Human IgG4: a structural perspective.

Science.gov (United States)

Davies, Anna M; Sutton, Brian J

2015-11-01

IgG4, the least represented human IgG subclass in serum, is an intriguing antibody with unique biological properties, such as the ability to undergo Fab-arm exchange and limit immune complex formation. The lack of effector functions, such as antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity, is desirable for therapeutic purposes. IgG4 plays a protective role in allergy by acting as a blocking antibody, and inhibiting mast cell degranulation, but a deleterious role in malignant melanoma, by impeding IgG1-mediated anti-tumor immunity. These findings highlight the importance of understanding the interaction between IgG4 and Fcγ receptors. Despite a wealth of structural information for the IgG1 subclass, including complexes with Fcγ receptors, and structures for intact antibodies, high-resolution crystal structures were not reported for IgG4-Fc until recently. Here, we highlight some of the biological properties of human IgG4, and review the recent crystal structures of IgG4-Fc. We discuss the unexpected conformations adopted by functionally important Cγ2 domain loops, and speculate about potential implications for the interaction between IgG4 and FcγRs. © 2015 The Authors. Immunological Reviews Published by John Wiley & Sons Ltd.

The 1.7 Å X-ray crystal structure of the porcine factor VIII C2 domain and binding analysis to anti-human C2 domain antibodies and phospholipid surfaces.

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Caileen M Brison

Full Text Available The factor VIII C2 domain is essential for binding to activated platelet surfaces as well as the cofactor activity of factor VIII in blood coagulation. Inhibitory antibodies against the C2 domain commonly develop following factor VIII replacement therapy for hemophilia A patients, or they may spontaneously arise in cases of acquired hemophilia. Porcine factor VIII is an effective therapeutic for hemophilia patients with inhibitor due to its low cross-reactivity; however, the molecular basis for this behavior is poorly understood. In this study, the X-ray crystal structure of the porcine factor VIII C2 domain was determined, and superposition of the human and porcine C2 domains demonstrates that most surface-exposed differences cluster on the face harboring the "non-classical" antibody epitopes. Furthermore, antibody-binding results illustrate that the "classical" 3E6 antibody can bind both the human and porcine C2 domains, although the inhibitory titer to human factor VIII is 41 Bethesda Units (BU/mg IgG versus 0.8 BU/mg IgG to porcine factor VIII, while the non-classical G99 antibody does not bind to the porcine C2 domain nor inhibit porcine factor VIII activity. Further structural analysis of differences between the electrostatic surface potentials suggest that the C2 domain binds to the negatively charged phospholipid surfaces of activated platelets primarily through the 3E6 epitope region. In contrast, the G99 face, which contains residue 2227, should be distal to the membrane surface. Phospholipid binding assays indicate that both porcine and human factor VIII C2 domains bind with comparable affinities, and the human K2227A and K2227E mutants bind to phospholipid surfaces with similar affinities as well. Lastly, the G99 IgG bound to PS-immobilized factor VIII C2 domain with an apparent dissociation constant of 15.5 nM, whereas 3E6 antibody binding to PS-bound C2 domain was not observed.

Roles for SH2 and SH3 domains in Lyn kinase association with activated FcepsilonRI in RBL mast cells revealed by patterned surface analysis.

Science.gov (United States)

Hammond, Stephanie; Wagenknecht-Wiesner, Alice; Veatch, Sarah L; Holowka, David; Baird, Barbara

2009-10-01

In mast cells, antigen-mediated cross-linking of IgE bound to its high-affinity surface receptor, FcepsilonRI, initiates a signaling cascade that culminates in degranulation and release of allergic mediators. Antigen-patterned surfaces, in which the antigen is deposited in micron-sized features on a silicon substrate, were used to examine the spatial relationship between clustered IgE-FcepsilonRI complexes and Lyn, the signal-initiating tyrosine kinase. RBL mast cells expressing wild-type Lyn-EGFP showed co-redistribution of this protein with clustered IgE receptors on antigen-patterned surfaces, whereas Lyn-EGFP containing an inhibitory point mutation in its SH2 domain did not significantly accumulate with the patterned antigen, and Lyn-EGFP with an inhibitory point mutation in its SH3 domain exhibited reduced interactions. Our results using antigen-patterned surfaces and quantitative cross-correlation image analysis reveal that both the SH2 and SH3 domains contribute to interactions between Lyn kinase and cross-linked IgE receptors in stimulated mast cells.

Differences in serum IgA responses to HIV-1 gp41 in elite controllers compared to viral suppressors on highly active antiretroviral therapy.

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Rafiq Nabi

Full Text Available Mechanisms responsible for natural control of human immunodeficiency type 1 (HIV replication in elite controllers (EC remain incompletely defined. To determine if EC generate high quality HIV-specific IgA responses, we used Western blotting to compare the specificities and frequencies of IgA to HIV antigens in serum of gender-, age- and race-matched EC and aviremic controllers (HC and viremic noncontrollers (HN on highly active antiretroviral therapy (HAART. Concentrations and avidity of IgA to HIV antigens were measured using ELISA or multiplex assays. Measurements for IgG were performed in parallel. EC were found to have stronger p24- and V1V2-specific IgG responses than HN, but there were no IgG differences for EC and HC. In contrast, IgA in EC serum bound more frequently to gp160 and gag proteins than IgA in HC or HN. The avidity of anti-gp41 IgA was also greater in EC, and these subjects had stronger IgA responses to the gp41 heptad repeat region 1 (HR1, a reported target of anti-bacterial RNA polymerase antibodies that cross react with gp41. However, EC did not demonstrate greater IgA responses to E. coli RNA polymerase or to peptides containing the shared LRAI sequence, suggesting that most of their HR1-specific IgA antibodies were not induced by intestinal microbiota. In both EC and HAART recipients, the concentrations of HIV-specific IgG were greater than HIV-specific IgA, but their avidities were comparable, implying that they could compete for antigen. Exceptions were C1 peptides and V1V2 loops. IgG and IgA responses to these antigens were discordant, with IgG reacting to V1V2, and IgA reacting to C1, especially in EC. Interestingly, EC with IgG hypergammaglobulinemia had greater HIV-specific IgA and IgG responses than EC with normal total IgG levels. Heterogeneity in EC antibody responses may therefore be due to a more focused HIV-specific B cell response in some of these individuals. Overall, these data suggest that development of

Repopulation with IgA-containing cells of bronchial and intestinal lamina propria after transfer of homologous peyer's patch and bronchial lymphocytes

International Nuclear Information System (INIS)

Rudzik, R.; Clancy, R.L.; Perey, D.Y.E.; Day, R.P.; Bienenstock, J.

1975-01-01

Transfer of 50 million rabbit allogeneic lymphocytes from either bronchus-associated lymphoid tissue (BALT) or Peyer's patches into 1000 R x-irradiated recipients results, 6 days later, in predominant repopulation of gut and bronchial lamina propria, as well as spleen, with IgA-containing cells. After repopulation with BALT or Peyer's patch cells, lymphoid follicles in both gut and lung showed peripheral cellular membrane type of fluorescence with fluorescein-conjugated anti-IgA antisera only. Six days after x-irradiation alone, little evidence of repopulation was seen and immunofluorescent qualitative observations of gut and lung, and quantitative data in the spleen, confirmed these findings. After transfer of 50 million lymph node cells, very few immunoglobulin-containing cells were seen in the gut or bronchial lamina propria. These results suggest that there may be a common mucosal immunologic system, and that repopulation of gut and lung lamina propria may be through the organized lymphoid tissue therein. (U.S.)

IgG4-related prostatitis progressed from localized IgG4-related lymphadenopathy.

Science.gov (United States)

Li, Dujuan; Kan, Yunzhen; Fu, Fangfang; Wang, Shuhuan; Shi, Ligang; Liu, Jie; Kong, Lingfei

2015-01-01

Immunoglobulin G4-related disease (IgG4-RD) is a recently described inflammatory disease involving multiple organs. Prostate involvement with IgG4-RD is very rare. In this report, we describe a case of IgG4-related prostatitis progressed from localized IgG4-related lymphadenopathy. This patient was present with urine retention symptoms. MRI and CT examination revealed the prostatic enlargement and the multiple lymphadenopathy. Serum IgG4 levels were elevated. Prostatic tissue samples resected both this time and less than 1 year earlier showed the same histological type of prostatitis with histopathologic and immunohistochemical findings characteristic of IgG4-RD. The right submandibular lymph nodes excised 2 years earlier were eventually proven to be follicular hyperplasia-type IgG4-related lymphadenopathy. This is the first case of IgG4-RD that began as localized IgG4-related lymphadenopathy and progressed into a systemic disease involving prostate and multiple lymph nodes. This patient showed a good response to steroid therapy. This leads us to advocate a novel pathogenesis of prostatitis, and a novel therapeutic approach against prostatitis. Pathologists and urologists should consider this disease entity in the patients with elevated serum IgG4 levels and the symptoms of prostatic hyperplasia to avoid ineffective medical or unnecessary surgical treatment.

Recombinant human immunoglobulin (Ig)A1 and IgA2 anti-D used for detection of IgA deficiency and anti-IgA

DEFF Research Database (Denmark)

Nielsen, Leif K; Dziegiel, Morten Hanefeld

2008-01-01

To avoid anaphylactic reactions, immunoglobulin (Ig)A-deficient patients with anti-IgA should be transfused with IgA-deficient blood components. There is a need for fast and robust assays for demonstration of IgA deficiency and for detection of anti-IgA.......To avoid anaphylactic reactions, immunoglobulin (Ig)A-deficient patients with anti-IgA should be transfused with IgA-deficient blood components. There is a need for fast and robust assays for demonstration of IgA deficiency and for detection of anti-IgA....

A simple method for determining polymeric IgA-containing immune complexes.

Science.gov (United States)

Sancho, J; Egido, J; González, E

1983-06-10

A simplified assay to measure polymeric IgA-immune complexes in biological fluids is described. The assay is based upon the specific binding of a secretory component for polymeric IgA. In the first step, multimeric IgA (monomeric and polymeric) immune complexes are determined by the standard Raji cell assay. Secondly, labeled secretory component added to the assay is bound to polymeric IgA-immune complexes previously fixed to Raji cells, but not to monomeric IgA immune complexes. To avoid false positives due to possible complement-fixing IgM immune complexes, prior IgM immunoadsorption is performed. Using anti-IgM antiserum coupled to CNBr-activated Sepharose 4B this step is not time-consuming. Polymeric IgA has a low affinity constant and binds weakly to Raji cells, as Scatchard analysis of the data shows. Thus, polymeric IgA immune complexes do not bind to Raji cells directly through Fc receptors, but through complement breakdown products, as with IgG-immune complexes. Using this method, we have been successful in detecting specific polymeric-IgA immune complexes in patients with IgA nephropathy (Berger's disease) and alcoholic liver disease, as well as in normal subjects after meals of high protein content. This new, simple, rapid and reproducible assay might help to study the physiopathological role of polymeric IgA immune complexes in humans and animals.

Recruitment practices for U.S. minority and underserved populations in NRG oncology: Results of an online survey

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Elise D. Cook

2018-06-01

Full Text Available Introduction: Cancer clinical trials (CCT provide much of the evidence for clinical guidelines and standards of care. But low levels of CCT participation are well documented, especially for minorities. Methods and materials: We conducted an online survey of 556 recruitment practices across the NRG Oncology network. Survey aims were 1 to learn how sites recruit minority/underserved populations; 2 to better understand the catchment areas of the NRG institutions; and 3 to aid in planning education programs for accrual of minority/underserved populations. Results: The survey response rate was 34.9%. The most effective methods reported for recruiting minority/underserved participants were patient navigators (44.4% and translators (38.9%. All institutions reported using a mechanism for eligibility screening and 71% of institutions reported using a screening/enrollment tracking system. CCT training was required at 78.1% and cultural competency training was required at 47.5% of responding institutions. Only 19.9% of sites used community partners to assist with minority recruitment and just 37.1% of respondents reported a defined catchment area. Sites reported very little race and ethnicity data. Conclusion: This NRG Oncology online survey provides useful data for improvements in trial enrollment and training to recruit minority/underserved populations to CCT. Areas for further investigation include web-based methods for recruitment and tracking, cultural competency training, definition of catchment areas, use of patient navigators, and community partnerships. The survey results will guide recruitment training programs.

Potential of Murine IgG1 and Human IgG4 to Inhibit the Classical Complement and Fcγ Receptor Activation Pathways

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Gina-Maria Lilienthal

2018-05-01

Full Text Available IgG antibodies (Abs mediate their effector functions through the interaction with Fcγ receptors (FcγRs and the complement factors. The main IgG-mediated complement activation pathway is induced through the binding of complement C1q to IgG Abs. This interaction is dependent on antigen-dependent hexamer formation of human IgG1 and IgG3 to increase the affinity for the six-headed C1q molecule. By contrast, human IgG4 fails to bind to C1q. Instead, it has been suggested that human IgG4 can block IgG1 and IgG3 hexamerization required for their binding to C1q and activating the complement. Here, we show that murine IgG1, which functionally resembles human IgG4 by not interacting with C1q, inhibits the binding of IgG2a, IgG2b, and IgG3 to C1q in vitro, and suppresses IgG2a-mediated complement activation in a hemolytic assay in an antigen-dependent and IgG subclass-specific manner. From this perspective, we discuss the potential of murine IgG1 and human IgG4 to block the complement activation as well as suppressive effects of sialylated IgG subclass Abs on FcγR-mediated immune cell activation. Accumulating evidence suggests that both mechanisms seem to be responsible for preventing uncontrolled IgG (autoAb-induced inflammation in mice and humans. Distinct IgG subclass distributions and functionally opposite IgG Fc glycosylation patterns might explain different outcomes of IgG-mediated immune responses and provide new therapeutic options through the induction, enrichment, or application of antigen-specific sialylated human IgG4 to prevent complement and FcγR activation as well.

C0 and C1 N-terminal Ig domains of myosin binding protein C exert different effects on thin filament activation.

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Harris, Samantha P; Belknap, Betty; Van Sciver, Robert E; White, Howard D; Galkin, Vitold E

2016-02-09

Mutations in genes encoding myosin, the molecular motor that powers cardiac muscle contraction, and its accessory protein, cardiac myosin binding protein C (cMyBP-C), are the two most common causes of hypertrophic cardiomyopathy (HCM). Recent studies established that the N-terminal domains (NTDs) of cMyBP-C (e.g., C0, C1, M, and C2) can bind to and activate or inhibit the thin filament (TF). However, the molecular mechanism(s) by which NTDs modulate interaction of myosin with the TF remains unknown and the contribution of each individual NTD to TF activation/inhibition is unclear. Here we used an integrated structure-function approach using cryoelectron microscopy, biochemical kinetics, and force measurements to reveal how the first two Ig-like domains of cMyPB-C (C0 and C1) interact with the TF. Results demonstrate that despite being structural homologs, C0 and C1 exhibit different patterns of binding on the surface of F-actin. Importantly, C1 but not C0 binds in a position to activate the TF by shifting tropomyosin (Tm) to the "open" structural state. We further show that C1 directly interacts with Tm and traps Tm in the open position on the surface of F-actin. Both C0 and C1 compete with myosin subfragment 1 for binding to F-actin and effectively inhibit actomyosin interactions when present at high ratios of NTDs to F-actin. Finally, we show that in contracting sarcomeres, the activating effect of C1 is apparent only once low levels of Ca(2+) have been achieved. We suggest that Ca(2+) modulates the interaction of cMyBP-C with the TF in the sarcomere.

Controlled delivery of fibroblast growth factor-1 and neuregulin-1 from biodegradable microparticles promotes cardiac repair in a rat myocardial infarction model through activation of endogenous regeneration.

Science.gov (United States)

Formiga, Fabio R; Pelacho, Beatriz; Garbayo, Elisa; Imbuluzqueta, Izaskun; Díaz-Herráez, Paula; Abizanda, Gloria; Gavira, Juan J; Simón-Yarza, Teresa; Albiasu, Edurne; Tamayo, Esther; Prósper, Felipe; Blanco-Prieto, Maria J

2014-01-10

Acidic fibroblast growth factor (FGF1) and neuregulin-1 (NRG1) are growth factors involved in cardiac development and regeneration. Microparticles (MPs) mediate cytokine sustained release, and can be utilized to overcome issues related to the limited therapeutic protein stability during systemic administration. We sought to examine whether the administration of microparticles (MPs) containing FGF1 and NRG1 could promote cardiac regeneration in a myocardial infarction (MI) rat model. We investigated the possible underlying mechanisms contributing to the beneficial effects of this therapy, especially those linked to endogenous regeneration. FGF1- and NRG1-loaded MPs were prepared using a multiple emulsion solvent evaporation technique. Seventy-three female Sprague-Dawley rats underwent permanent left anterior descending coronary artery occlusion, and MPs were intramyocardially injected in the peri-infarcted zone four days later. Cardiac function, heart tissue remodeling, revascularization, apoptosis, cardiomyocyte proliferation, and stem cell homing were evaluated one week and three months after treatment. MPs were shown to efficiently encapsulate FGF1 and NRG1, releasing the bioactive proteins in a sustained manner. Three months after treatment, a statistically significant improvement in cardiac function was detected in rats treated with growth factor-loaded MPs (FGF1, NRG1, or FGF1/NRG1). The therapy led to inhibition of cardiac remodeling with smaller infarct size, a lower fibrosis degree and induction of tissue revascularization. Cardiomyocyte proliferation and progenitor cell recruitment were detected. Our data support the therapeutic benefit of NRG1 and FGF1 when combined with protein delivery systems for cardiac regeneration. This approach could be scaled up for use in pre-clinical and clinical studies. © 2013.

TgrC1 mediates cell-cell adhesion by interacting with TgrB1 via mutual IPT/TIG domains during development of Dictyostelium discoideum.

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Chen, Gong; Wang, Jun; Xu, Xiaoqun; Wu, Xiangfu; Piao, Ruihan; Siu, Chi-Hung

2013-06-01

Cell-cell adhesion plays crucial roles in cell differentiation and morphogenesis during development of Dictyostelium discoideum. The heterophilic adhesion protein TgrC1 (Tgr is transmembrane, IPT, IG, E-set, repeat protein) is expressed during cell aggregation, and disruption of the tgrC1 gene results in the arrest of development at the loose aggregate stage. We have used far-Western blotting coupled with MS to identify TgrB1 as the heterophilic binding partner of TgrC1. Co-immunoprecipitation and pull-down studies showed that TgrB1 and TgrC1 are capable of binding with each other in solution. TgrB1 and TgrC1 are encoded by a pair of adjacent genes which share a common promoter. Both TgrB1 and TgrC1 are type I transmembrane proteins, which contain three extracellular IPT/TIG (immunoglobulin, plexin, transcription factor-like/transcription factor immunoglobulin) domains. Antibodies raised against TgrB1 inhibit cell reassociation at the post-aggregation stage of development and block fruiting body formation. Ectopic expression of TgrB1 and TgrC1 driven by the actin15 promoter leads to heterotypic cell aggregation of vegetative cells. Using recombinant proteins that cover different portions of TgrB1 and TgrC1 in binding assays, we have mapped the cell-binding regions in these two proteins to Lys(537)-Ala(783) in TgrB1 and Ile(336)-Val(360) in TgrC1, corresponding to their respective TIG3 and TIG2 domain.

Role of anti-domain 1-β2 glycoprotein I antibodies in the diagnosis and risk stratification of antiphospholipid syndrome.

Science.gov (United States)

De Craemer, A-S; Musial, J; Devreese, K M J

2016-09-01

Essentials Antibodies to domain 1 of β2 glycoprotein I (aD1) are a subset of antiphospholipid antibodies. We evaluated the added diagnostic value of an automated aD1 assay in antiphospholipid syndrome. AD1 IgG correctly classifies patients at risk for thrombosis. Agreement between aD1 and aβ2GPI IgG is high, limiting the added value of aD1 in our setting. Click to hear Professor de Groot's perspective on new mechanistic understanding in antiphospholipid syndrome Background Laboratory diagnosis of antiphospholipid syndrome (APS) includes lupus anticoagulant (LAC), anticardiolipin (aCL) or anti-β2 glycoprotein I (aβ2 GPI) antibodies. Antibodies targeting domain 1 of β2 GPI (aD1) constitute a pathogenic subset of autoantibodies. Objectives In this cohort study, we determined the clinical performance characteristics, additional diagnostic value and the contribution to APS risk stratification of an automated aD1 assay. Patients/Methods LAC, aCL, aβ2 GPI and aD1 IgG were measured in 101 APS patients, 123 patients with autoimmune disorders, 82 diseased controls and 120 healthy controls. aD1 antibodies were detected by QUANTA Flash(®) Beta2GPI-Domain 1 chemiluminescence immunoassay. Results With a cut-off value of 20.0 CU, the aD1 IgG assay identifies APS patients in a clinically affected patient cohort with a sensitivity of 53.5% and specificity of 98.8%. It implied a high odds ratio (OR) for clinical events (OR, 17.0; 95% confidence interval [CI], 7.1-40.5). aD1 IgG did not add diagnostic value to the formal aPL panel because aβ2 GPI IgG was nearly as specific but more sensitive for APS (sensitivity 56.4%) with a higher OR for clinical events (36.2; 95% CI, 11.1-117.9). High aD1 titers identify triple-positive patients and patients with thrombosis in a β2 GPI-dependent LAC-positive population. Agreement between aD1 IgG and aβ2 GPI IgG was high (positive and negative agreement 91.7% and 98.4%, respectively). Conclusion Detection of aD1 IgG correctly classifies

UBA domain containing proteins in fission yeast

DEFF Research Database (Denmark)

Hartmann-Petersen, Rasmus; Semple, Colin A M; Ponting, Chris P

2003-01-01

characterised on both the functional and structural levels. One example of a widespread ubiquitin binding module is the ubiquitin associated (UBA) domain. Here, we discuss the approximately 15 UBA domain containing proteins encoded in the relatively small genome of the fission yeast Schizosaccharomyces pombe...

IgE vs IgG4 epitopes of the peanut allergen Ara h 1 in patients with severe allergy

DEFF Research Database (Denmark)

Bøgh, Katrine Lindholm; Nielsen, H.; Eiwegger, T.

2013-01-01

to the allergen. However, recent studies have demonstrated the very importance of the IgG4-epitope affinity for the blocking ability. Studies comparing IgE and IgG4 binding epitopes mainly focus on the identification of linear epitopes. Peanut allergy is one of the most severe and persistent forms of food allergy....... The importance of conformational epitopes, of the major peanut allergen Ara h 1, has been demonstrated. The aim of this study was to compare Ara h 1-specific epitope patterns for IgE and IgG4 in patients with severe peanut allergy applying a method suitable to identify both linear and conformational epitopes....... Methods: Ara h 1-specific IgE and IgG4 epitope patterns were examined by competitive immunoscreening of a phage-displayed random 7-mer peptide library using polyclonal IgE and IgG4 from three individual patients suffering from severe peanut allergy. The resulting peptide sequences were mapped...

Effect of pH, temperature, and salt on the stability of Escherichia coli- and Chinese hamster ovary cell-derived IgG1 Fc.

Science.gov (United States)

Li, Cynthia H; Narhi, Linda O; Wen, Jie; Dimitrova, Mariana; Wen, Zai-qing; Li, Jenny; Pollastrini, Joseph; Nguyen, Xichdao; Tsuruda, Trace; Jiang, Yijia

2012-12-18

The circulation half-life of a potential therapeutic can be increased by fusing the molecule of interest (an active peptide, the extracellular domain of a receptor, an enzyme, etc.) to the Fc fragment of a monoclonal antibody. For the fusion protein to be a successful therapeutic, it must be stable to process and long-term storage conditions, as well as to physiological conditions. The stability of the Fc used is critical for obtaining a successful therapeutic protein. The effects of pH, temperature, and salt on the stabilities of Escherichia coli- and Chinese hamster ovary cell (CHO)-derived IgG1 Fc high-order structure were probed using a variety of biophysical techniques. Fc molecules derived from both E. coli and CHO were compared. The IgG1 Fc molecules from both sources (glycosylated and aglycosylated) are folded at neutral pH and behave similarly upon heat- and low pH-induced unfolding. The unfolding of both IgG1 Fc molecules occurs via a multistep unfolding process, with the tertiary structure and C(H)2 domain unfolding first, followed by changes in the secondary structure and C(H)3 domain. The acid-induced unfolding of IgG1 Fc molecules is only partially reversible, with the formation of high-molecular weight species. The CHO-derived Fc protein (glycosylated) is more compact (smaller hydrodynamic radius) than the E. coli-derived protein (aglycosylated) at neutral pH. Unfolding is dependent on pH and salt concentration. The glycosylated C(H)2 domain melts at a temperature 4-5 °C higher than that of the aglycosylated domain, and the low-pH-induced unfolding of the glycosylated Fc molecule occurs at a pH ~0.5 pH unit lower than that of the aglycosylated protein. The difference observed between E. coli- and CHO-derived Fc molecules primarily involves the C(H)2 domain, where the glycosylation of the Fc resides.

Type I CD20 Antibodies Recruit the B Cell Receptor for Complement-Dependent Lysis of Malignant B Cells

NARCIS (Netherlands)

Engelberts, Patrick J.; Voorhorst, Marleen; Schuurman, Janine; van Meerten, Tom; Bakker, Joost M.; Vink, Tom; Mackus, Wendy J. M.; Breij, Esther C. W.; Derer, Stefanie; Valerius, Thomas; van de Winkel, Jan G. J.; Parren, Paul W. H. I.; Beurskens, Frank J.

2016-01-01

Human IgG1 type I CD20 Abs, such as rituximab and ofatumumab (OFA), efficiently induce complement-dependent cytotoxicity (CDC) of CD20(+) B cells by binding of C1 to hexamerized Fc domains. Unexpectedly, we found that type I CD20 Ab F(ab ')2 fragments, as well as C1q-binding-deficient IgG mutants,

Recombinant spider silk genetically functionalized with affinity domains.

Science.gov (United States)

Jansson, Ronnie; Thatikonda, Naresh; Lindberg, Diana; Rising, Anna; Johansson, Jan; Nygren, Per-Åke; Hedhammar, My

2014-05-12

Functionalization of biocompatible materials for presentation of active protein domains is an area of growing interest. Herein, we describe a strategy for functionalization of recombinant spider silk via gene fusion to affinity domains of broad biotechnological use. Four affinity domains of different origin and structure; the IgG-binding domains Z and C2, the albumin-binding domain ABD, and the biotin-binding domain M4, were all successfully produced as soluble silk fusion proteins under nondenaturing purification conditions. Silk films and fibers produced from the fusion proteins were demonstrated to be chemically and thermally stable. Still, the bioactive domains are concluded to be folded and accessible, since their respective targets could be selectively captured from complex samples, including rabbit serum and human plasma. Interestingly, materials produced from mixtures of two different silk fusion proteins displayed combined binding properties, suggesting that tailor-made materials with desired stoichiometry and surface distributions of several binding domains can be produced. Further, use of the IgG binding ability as a general mean for presentation of desired biomolecules could be demonstrated for a human vascular endothelial growth factor (hVEGF) model system, via a first capture of anti-VEGF IgG to silk containing the Z-domain, followed by incubation with hVEGF. Taken together, this study demonstrates the potential of recombinant silk, genetically functionalized with affinity domains, for construction of biomaterials capable of presentation of almost any desired biomolecule.

In vivo infection of IgG-containing cells by Jembrana disease virus during acute infection

International Nuclear Information System (INIS)

Desport, Moira; Tenaya, I.W. Masa; McLachlan, Alexander; McNab, Tegan J.; Rachmat, Judhi; Hartaningsih, Nining; Wilcox, Graham E.

2009-01-01

Jembrana disease virus (JDV) is an unusual bovine lentivirus which causes a non-follicular proliferation of lymphocytes, a transient immunosuppression and a delayed humoral response in infected Bali cattle in Indonesia. A double-immunofluorescent labeling method was developed to identify the subset of mononuclear cells in which the viral capsid protein could be detected. Viral antigen was present in pleomorphic centroblast-like cells which were identified as IgG-containing cells, including plasma cells, in lymphoid tissues. There was no evidence of infection of CD3 + T-cells or MAC387 + monocytes in tissues but large vacuolated cells with a macrophage-like morphology in the lung were found to contain viral antigen although they could not be shown conclusively to be infected. The tropism of JDV for mature IgG-containing cells may be relevant to understanding the pathogenesis of Jembrana disease, the delayed antibody responses and the genetic composition of this atypical lentivirus.

B1 Cell IgE Impedes Mast Cell-Mediated Enhancement of Parasite Expulsion through B2 IgE Blockade

Directory of Open Access Journals (Sweden)

Rebecca K. Martin

2018-02-01

Full Text Available Helminth infection is known for generating large amounts of poly-specific IgE. Here we demonstrate that innate-like B1 cells are responsible for this IgE production during infection with the nematode parasites Nippostrongylus brasiliensis and Heligmosomoides polygyrus bakeri. In vitro analysis of B1 cell immunoglobulin class switch recombination to IgE demonstrated a requirement for anti-CD40 and IL-4 that was further enhanced when IL-5 was added or when the B1 source was helminth infected mice. An IL-25-induced upregulation of IgE in B1 cells was also demonstrated. In T cell-reconstituted RAG1−/− mice, N. brasiliensis clearance was enhanced with the addition of B2 cells in an IgE-dependent manner. This enhanced clearance was impeded by reconstitution with IgE sufficient B1 cells. Mucosal mast cells mediated the B2 cell enhancement of clearance in the absence of B1 cells. The data support B1 cell IgE secretion as a regulatory response exploited by the helminth.

CUB-domain-containing protein 1 overexpression in solid cancers promotes cancer cell growth by activating Src family kinases.

Science.gov (United States)

Leroy, C; Shen, Q; Strande, V; Meyer, R; McLaughlin, M E; Lezan, E; Bentires-Alj, M; Voshol, H; Bonenfant, D; Alex Gaither, L

2015-10-29

The transmembrane glycoprotein, CUB (complement C1r/C1s, Uegf, Bmp1) domain-containing protein 1 (CDCP1) is overexpressed in several cancer types and is a predictor of poor prognosis for patients on standard of care therapies. Phosphorylation of CDCP1 tyrosine sites is induced upon loss of cell adhesion and is thought to be linked to metastatic potential of tumor cells. Using a tyrosine-phosphoproteomics screening approach, we characterized the phosphorylation state of CDCP1 across a panel of breast cancer cell lines. We focused on two phospho-tyrosine pTyr peptides of CDCP1, containing Tyr707 and Tyr806, which were identified in all six lines, with the human epidermal growth factor 2-positive HCC1954 cells showing a particularly high phosphorylation level. Pharmacological modulation of tyrosine phosphorylation indicated that, the Src family kinases (SFKs) were found to phosphorylate CDCP1 at Tyr707 and Tyr806 and play a critical role in CDCP1 activity. We demonstrated that CDCP1 overexpression in HEK293 cells increases global phosphotyrosine content, promotes anchorage-independent cell growth and activates several SFK members. Conversely, CDCP1 downregulation in multiple solid cancer cell lines decreased both cell growth and SFK activation. Analysis of primary human tumor samples demonstrated a correlation between CDCP1 expression, SFK and protein kinase C (PKC) activity. Taken together, our results suggest that CDCP1 overexpression could be an interesting therapeutic target in multiple solid cancers and a good biomarker to stratify patients who could benefit from an anti-SFK-targeted therapy. Our data also show that multiple tyrosine phosphorylation sites of CDCP1 are important for the functional regulation of SFKs in several tumor types.

Mobilization of immunoglobulin (Ig)-containing plasma cells in Harderian gland, cecal tonsil and trachea of broilers vaccinated with Newcastle Disease Vaccine.

Science.gov (United States)

Nasrin, M; Khan, M Z I; Siddiqi, M N H; Masum, M A

2013-06-01

Immunohistochemical studies of Harderian gland, cecal tonsil and trachea of various groups of broiler chickens and the response of Baby Chick Ranikhet Disease Vaccines (BCRDV) on the mobilization of Igs-cells during postnatal development of organs was investigated in the Dept. of Anatomy and Histology, Bangladesh Agricultural University, Mymensingh. In this study twelve chickens were grouped into vaccinated broilers (D14 and D28) which had received vaccines first at D3 of age and a booster dose given at D13; and non-vaccinated broilers (D1) which had not been vaccinated. In this study, it was observed that the frequency and distribution of Igs-positive cells were higher at D14 and at D28 rather than D1. Among Igs-positive cells, the IgG-positive cells were significantly higher than IgM and IgA-positive cells in the Harderian gland of D14 and D28 groups of chickens, however, in day-old chickens, the frequency of IgM-positive cells in this gland were greater. In the cecal tonsil, the frequency and distribution of IgG-positive cells were significantly higher than IgA- and IgM-positive cells both at D14 and D28 ages of chicken. On the other hand, in day-old chickens, the frequency and distribution of IgA-positive cells were insignificantly greater, followed by IgM and IgG-positive cells. In the trachea, few immunoglobulin-containing plasma cells were distributed in the subepithelial layer. IgM-positive cells were higher followed by IgG and IgA-positive cells in the trachea in D14 and D28 groups of chickens. In the same organ, IgG-positive plasma cells were greater than IgA and IgM-positive cells at one-day old. When the data for Harderian gland, cecal tonsil and trachea were compared statistically, it was observed that Igs-positive cells were statistically more common in cecal tonsils in day old chickens, and with the advancement of age, Igs-positive cells were found more in the Harderian gland. In conclusion, with the advancement of age in chickens the Harderian gland

Soluble IgM links apoptosis to complement activation in early alcoholic liver disease in mice.

Science.gov (United States)

Smathers, Rebecca L; Chiang, Dian J; McMullen, Megan R; Feldstein, Ariel E; Roychowdhury, Sanjoy; Nagy, Laura E

2016-04-01

Ethanol feeding in mice activates complement via C1q binding to apoptotic cells in the liver; complement contributes to ethanol-induced inflammation and injury. Despite the critical role of C1q in ethanol-induced injury, the mechanism by which ethanol activates C1q remains poorly understood. Secretory IgM (sIgM), traditionally considered to act as an anti-microbial, also has critical housekeeping functions, facilitating clearance of apoptotic cells, at least in part through activation of C1q. Therefore, we hypothesized that (1) ethanol-induced apoptosis in the liver recruits sIgM, facilitating the activation of C1q and complement and (2) C1INH (C1 esterase inhibitor), which inhibits C1 functional activity, prevents complement activation and decreases ethanol-induced liver injury. Female C57BL/6 wild-type, C1qa(-/-), BID(-/-) and sIgM(-/-) mice were fed ethanol containing liquid diets or pair-fed control diets. C1INH or vehicle was given via tail vein injection to ethanol- or pair-fed wild-type mice at 24 and 48h prior to euthanasia. Ethanol exposure increased apoptosis in the liver, as well as the accumulation of IgM in the liver. In the early stages of ethanol feeding, C1q co-localized with IgM in the peri-sinusoidal space of the liver and accumulation of IgM and C3b was dependent on ethanol-induced BID-dependent apoptosis. sIgM(-/-) mice were protected from both ethanol-induced activation of complement and early ethanol-induced liver injury when compared to wild-type mice. Treatment with C1INH also decreased hepatic C3b deposition and ethanol-induced injury. These data indicate that sIgM contributes to activation of complement and ethanol-induced increases in inflammatory cytokine expression and hepatocyte injury in the early stages of ethanol-induced liver injury. Copyright © 2016 Elsevier Ltd. All rights reserved.

Low-dose oral tolerance due to antigen in the diet suppresses differentially the cholera toxin-adjuvantized IgE, IgA and IgG response

DEFF Research Database (Denmark)

Christensen, Hanne Risager; Kjær, Tanja; Frøkiær, Hanne

2003-01-01

Background: Cholera toxin (CT) is used as a mucosal adjuvant amongst other applications for studying food allergy because oral administration of antigen with CT induces an antigen-specific type 2 response, including IgE and IgA production. Priorly established oral tolerance due to antigen...... soy-trypsin inhibitor (KSTI) (F0 mice) and mice fed a soy-free diet (F2 mice) were orally immunized with KSTI and CT. KSTI-specific serum IgG1, IgG2a, IgA and IgE and fecal IgA were monitored. KSTI-stimulated cell proliferation and interleukin (IL)-6 production were determined. Results: The anti...... immunizations. However, cell proliferation and IL-6 production were clearly suppressed even after five immunizations. Conclusions: Priorly established low-dose oral tolerance considerably suppressed the CT-adjuvantized KSTI-specific IgE, IgA and cellular immune response but only weakly and transiently the Ig...

Crystallization and preliminary X-ray crystallographic study of the wild type and two mutants of the CP1 hydrolytic domain from Aquifex aeolicus leucyl-tRNA synthetase

Energy Technology Data Exchange (ETDEWEB)

Cura, Vincent; Olieric, Natacha; Guichard, Alexandre [Département de Biologie et Génomique Structurales, UMR 7104, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP Strasbourg, 1 Rue Laurent Fries, 67404 Illkirch (France); Wang, En-Duo [State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031 (China); Moras, Dino [Département de Biologie et Génomique Structurales, UMR 7104, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP Strasbourg, 1 Rue Laurent Fries, 67404 Illkirch (France); Eriani, Gilbert [Architecture et Réactivité de l’ARN, UPR 9002, Institut de Biologie Moléculaire et Cellulaire du CNRS, 15 Rue René Descartes, 67084 Strasbourg (France); Cavarelli, Jean, E-mail: cava@igbmc.u-strasbg.fr [Département de Biologie et Génomique Structurales, UMR 7104, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP Strasbourg, 1 Rue Laurent Fries, 67404 Illkirch (France)

2005-10-01

The wild-type editing CP1 domain of A. aeolicus leucyl-tRNA synthetase and two mutant CP1 domains have been overexpressed, purified and crystallized. X-ray diffraction data have been collected to 1.8 Å, which has enabled determination of the structures by molecular replacement. The editing or hydrolytic CP1 domain of leucyl-tRNA synthetase (LeuRS) hydrolyses several misactivated amino acids. The CP1 domain of Aquifex aeolicus LeuRS was expressed, purified and crystallized by the hanging-drop vapour-diffusion method using ammonium sulfate as precipitant. Crystals belong to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 38.8, b = 98.4, c = 116.7 Å. Crystals diffract to beyond 1.8 Å resolution and contain two monomers in the asymmetric unit. Two CP1 mutants in which a conserved threonine residue essential for the fidelity of the hydrolytic pathway is mutated to alanine or glutamic acid have also been expressed and crystallized. Crystals of the two CP1 mutants are isomorphs of the wild type and diffract to beyond 1.9 Å resolution. All structures were solved by molecular-replacement techniques.

Crystallization and preliminary X-ray crystallographic study of the wild type and two mutants of the CP1 hydrolytic domain from Aquifex aeolicus leucyl-tRNA synthetase

International Nuclear Information System (INIS)

Cura, Vincent; Olieric, Natacha; Guichard, Alexandre; Wang, En-Duo; Moras, Dino; Eriani, Gilbert; Cavarelli, Jean

2005-01-01

The wild-type editing CP1 domain of A. aeolicus leucyl-tRNA synthetase and two mutant CP1 domains have been overexpressed, purified and crystallized. X-ray diffraction data have been collected to 1.8 Å, which has enabled determination of the structures by molecular replacement. The editing or hydrolytic CP1 domain of leucyl-tRNA synthetase (LeuRS) hydrolyses several misactivated amino acids. The CP1 domain of Aquifex aeolicus LeuRS was expressed, purified and crystallized by the hanging-drop vapour-diffusion method using ammonium sulfate as precipitant. Crystals belong to space group P2 1 2 1 2 1 , with unit-cell parameters a = 38.8, b = 98.4, c = 116.7 Å. Crystals diffract to beyond 1.8 Å resolution and contain two monomers in the asymmetric unit. Two CP1 mutants in which a conserved threonine residue essential for the fidelity of the hydrolytic pathway is mutated to alanine or glutamic acid have also been expressed and crystallized. Crystals of the two CP1 mutants are isomorphs of the wild type and diffract to beyond 1.9 Å resolution. All structures were solved by molecular-replacement techniques

A conserved gene family encodes transmembrane proteins with fibronectin, immunoglobulin and leucine-rich repeat domains (FIGLER

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Haga Christopher L

2007-09-01

Full Text Available Abstract Background In mouse the cytokine interleukin-7 (IL-7 is required for generation of B lymphocytes, but human IL-7 does not appear to have this function. A bioinformatics approach was therefore used to identify IL-7 receptor related genes in the hope of identifying the elusive human cytokine. Results Our database search identified a family of nine gene candidates, which we have provisionally named fibronectin immunoglobulin leucine-rich repeat (FIGLER. The FIGLER 1–9 genes are predicted to encode type I transmembrane glycoproteins with 6–12 leucine-rich repeats (LRR, a C2 type Ig domain, a fibronectin type III domain, a hydrophobic transmembrane domain, and a cytoplasmic domain containing one to four tyrosine residues. Members of this multichromosomal gene family possess 20–47% overall amino acid identity and are differentially expressed in cell lines and primary hematopoietic lineage cells. Genes for FIGLER homologs were identified in macaque, orangutan, chimpanzee, mouse, rat, dog, chicken, toad, and puffer fish databases. The non-human FIGLER homologs share 38–99% overall amino acid identity with their human counterpart. Conclusion The extracellular domain structure and absence of recognizable cytoplasmic signaling motifs in members of the highly conserved FIGLER gene family suggest a trophic or cell adhesion function for these molecules.

Novel receptor-like kinases in cacao contain PR-1 extracellular domains.

Science.gov (United States)

Teixeira, Paulo José Pereira Lima; Costa, Gustavo Gilson Lacerda; Fiorin, Gabriel Lorencini; Pereira, Gonçalo Amarante Guimarães; Mondego, Jorge Maurício Costa

2013-08-01

Members of the pathogenesis-related protein 1 (PR-1) family are well-known markers of plant defence responses, forming part of the arsenal of the secreted proteins produced on pathogen recognition. Here, we report the identification of two cacao (Theobroma cacao L.) PR-1s that are fused to transmembrane regions and serine/threonine kinase domains, in a manner characteristic of receptor-like kinases (RLKs). These proteins (TcPR-1f and TcPR-1g) were named PR-1 receptor kinases (PR-1RKs). Phylogenetic analysis of RLKs and PR-1 proteins from cacao indicated that PR-1RKs originated from a fusion between sequences encoding PR-1 and the kinase domain of a LecRLK (Lectin Receptor-Like Kinase). Retrotransposition marks surround TcPR-1f, suggesting that retrotransposition was involved in the origin of PR-1RKs. Genes with a similar domain architecture to cacao PR-1RKs were found in rice (Oryza sativa), barrel medic (Medicago truncatula) and a nonphototrophic bacterium (Herpetosiphon aurantiacus). However, their kinase domains differed from those found in LecRLKs, indicating the occurrence of convergent evolution. TcPR-1g expression was up-regulated in the biotrophic stage of witches' broom disease, suggesting a role for PR-1RKs during cacao defence responses. We hypothesize that PR-1RKs transduce a defence signal by interacting with a PR-1 ligand. © 2013 BSPP AND JOHN WILEY & SONS LTD.

Copper Metabolism Domain-Containing 1 Represses Genes That Promote Inflammation and Protects Mice From Colitis and Colitis-Associated Cancer

NARCIS (Netherlands)

Li, Haiying; Chan, Lillienne; Bartuzi, Paulina; Melton, Shelby D.; Weber, Axel; Ben-Shlomo, Shani; Varol, Chen; Raetz, Megan; Mao, Xicheng; Starokadomskyy, Petro; van Sommeren, Suzanne; Mokadem, Mohamad; Schneider, Heike; Weisberg, Reid; Westra, Harm-Jan; Esko, Tonu; Metspalu, Andres; Magadi Gopalaiah, Vinod Kumar; Faubion, William A.; Yarovinsky, Felix; Hofker, Marten; Wijmenga, Cisca; Kracht, Michael; Franke, Lude; Aguirre, Vincent; Weersma, Rinse K.; Gluck, Nathan; van de Sluis, Bart; Burstein, Ezra

BACKGROUND & AIMS: Activation of the transcription factor nuclear factor-kappa B (NF-kappa B) has been associated with the development of inflammatory bowel disease (IBD). Copper metabolism MURR1 domain containing 1 (COMMD1), a regulator of various transport pathways, has been shown to limit

Immunization with gingipain A hemagglutinin domain of Porphyromonas gingivalis induces IgM antibodies binding to malondialdehyde-acetaldehyde modified low-density lipoprotein.

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Mikael Kyrklund

Full Text Available Treatment of periodontitis has beneficial effects on systemic inflammation markers that relate to progression of atherosclerosis. We aimed to investigate whether immunization with A hemagglutinin domain (Rgp44 of Porphyromonas gingivalis (Pg, a major etiologic agent of periodontitis, would lead to an antibody response cross-reacting with oxidized low-density lipoprotein (OxLDL and how it would affect the progression of atherosclerosis in low-density lipoprotein receptor-deficient (LDLR-/- mice. The data revealed a prominent IgM but not IgG response to malondialdehyde-acetaldehyde modified LDL (MAA-LDL after Rgp44 and Pg immunizations, implying that Rgp44/Pg and MAA adducts may share cross-reactive epitopes that prompt IgM antibody production and consequently confer atheroprotection. A significant negative association was observed between atherosclerotic lesion and plasma IgA to Rgp44 in Rgp44 immunized mice, supporting further the anti-atherogenic effect of Rgp44 immunization. Plasma IgA levels to Rgp44 and to Pg in both Rgp44- and Pg-immunized mice were significantly higher than those in saline control, suggesting that IgA to Rgp44 could be a surrogate marker of immunization in Pg-immunized mice. Distinct antibody responses in plasma IgA levels to MAA-LDL, to Pg lipopolysaccharides (Pg-LPS, and to phosphocholine (PCho were observed after Rgp44 and Pg immunizations, indicating that different immunogenic components between Rpg44 and Pg may behave differently in regard of their roles in the development of atherosclerosis. Immunization with Rgp44 also displayed atheroprotective features in modulation of plaque size through association with plasma levels of IL-1α whereas whole Pg bacteria achieved through regulation of anti-inflammatory cytokine levels of IL-5 and IL-10. The present study may contribute to refining therapeutic approaches aiming to modulate immune responses and inflammatory/anti-inflammatory processes in atherosclerosis.

Immunohistochemical Localization of Fibrinogen C Domain Containing 1 on Epithelial and Mucosal Surfaces in Human Tissues

DEFF Research Database (Denmark)

von Huth, Sebastian; Moeller, Jesper B; Schlosser, Anders

2018-01-01

Fibrinogen C domain containing 1 (FIBCD1) is a transmembrane receptor that binds chitin and other acetylated compounds with high affinity. FIBCD1 has previously been shown to be present in the epithelium of the gastrointestinal tract. In the present study, we performed a detailed analysis...... high expression of FIBCD1 and also mesodermal-derived cells in the genitourinary system and ectodermal-derived epidermis and sebaceous glands cells expressed FIBCD1. In some columnar epithelial cells, for example, in the salivary gland and gall bladder, the FIBCD1 expression was clearly polarized...

SU-F-T-351: Establishing a Workflow for IMRT Pre-Treatment Reviews for NRG-GY006 Clinical Trial

Energy Technology Data Exchange (ETDEWEB)

Giaddui, T [Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States); Li, N; Moore, K; Mell, L [University of California, San Diego, San Diego, CA (United States); Curry, K [MIM Software, Inc., Clevealand, OH (United States); Leath, C [University of Alabama at Birmingham, Birmingham, AL (United States); Kunos, C [Northeastern Ohio University College, Clevealand, OH (United States); Xiao, Y [University of Pennsylvania, Philadelphia, PA (United States)

2016-06-15

was supported by grants U24CA180803 (IROC), UG1CA189867 (NCORP), U10CA180868 (NRG Oncology Operations), U10CA180822 (NRG Oncology SDMC) from the National Cancer Institute (NCI) and PA CURE grant.

SU-F-T-351: Establishing a Workflow for IMRT Pre-Treatment Reviews for NRG-GY006 Clinical Trial

International Nuclear Information System (INIS)

Giaddui, T; Li, N; Moore, K; Mell, L; Curry, K; Leath, C; Kunos, C; Xiao, Y

2016-01-01

was supported by grants U24CA180803 (IROC), UG1CA189867 (NCORP), U10CA180868 (NRG Oncology Operations), U10CA180822 (NRG Oncology SDMC) from the National Cancer Institute (NCI) and PA CURE grant

Inhibition of STAT3 Signaling Reduces IgA1 Autoantigen Production in IgA Nephropathy

Directory of Open Access Journals (Sweden)

Koshi Yamada

2017-11-01

Discussion: Our results revealed that IL-6−induced aberrant activation of STAT3-mediated overproduction of galactose-deficient IgA1. STAT3 signaling pathway may thus represent a new target for disease-specific therapy of IgA nephropathy.

Core alpha1-->3-fucose is a common modification of N-glycans in parasitic helminths and constitutes an important epitope for IgE from Haemonchus contortus infected sheep

NARCIS (Netherlands)

van Die, I.; Gomord, V.; Kooyman, F. N.; van den Berg, T. K.; Cummings, R. D.; Vervelde, L.

1999-01-01

Synthesis of parasite specific IgE plays a critical role in the defence against helminth infections. We report here that IgE from serum from Schistosoma mansoni infected mice and Haemonchus contortus infected sheep recognizes complex-type N-glycans from Arabidopsis thaliana, which contain

Mast cells contribute to the mucosal adjuvant effect of CTA1-DD after IgG-complex formation.

Science.gov (United States)

Fang, Yu; Larsson, Lisa; Mattsson, Johan; Lycke, Nils; Xiang, Zou

2010-09-01

Mast cell activation is one of the most dramatic immune-mediated responses the body can encounter. In the worst scenario (i.e., anaphylaxis), this response is fatal. However, the importance of mast cells as initiators and effectors of both innate and adaptive immunity in healthy individuals has recently been appreciated. It was reported that mast cell activation can be used as an adjuvant to promote Ag-specific humoral immune responses upon vaccination. In this study, we have used a clinically relevant mucosal adjuvant, cholera toxin A1 subunit (CTA1)-DD, which is a fusion protein composed of CTA1, the ADP-ribosylating part of cholera toxin, and DD, two Ig-binding domains derived from Staphylococcus aureus protein A. CTA1-DD in combination with polyclonal IgG induced degranulation and production of TNF-alpha from mouse mast cells. Furthermore, CTA1-DD and polyclonal IgG complex induced mast cell degranulation in mouse skin tissue and nasal mucosa. We also found that intranasal immunization with hapten (4-hydroxy-3-nitrophenyl) acetyl (NP) coupled to chicken gammaglobulin admixed with CTA1-DD complexed with polyclonal IgG greatly enhanced serum IgG anti-NP Ab responses and stimulated higher numbers of NP-specific plasma cells in the bone marrow as compared with that observed in mice immunized with NP-chicken gammaglobulin with CTA1-DD alone. This CTA1-DD/IgG complex-mediated enhancement was mast cell dependent because it was absent in mast cell-deficient Kit(W-sh/W-sh) mice. In conclusion, our data suggest that a clinically relevant adjuvant, CTA1-DD, exerts additional augmenting effects through activation of mucosal mast cells, clearly demonstrating that mast cells could be further exploited for improving the efficacy of mucosal vaccines.

IgG4-Seronegative Autoimmune Pancreatitis and Sclerosing Cholangitis

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Allon Kahn

2015-01-01

Full Text Available IgG4-related disease is a relatively novel clinical entity whose gastrointestinal manifestations include type 1 autoimmune pancreatitis (AIP and IgG4-associated sclerosing cholangitis. The presence of elevated serum IgG4 is suggestive but not essential for the diagnosis of type 1 AIP and is a pervasive feature of the proposed diagnostic criteria. The differential diagnosis of type 1 AIP includes malignant conditions, emphasizing the importance of a deliberate, comprehensive evaluation. Management of patients with a suggestive clinical presentation, but without serum IgG4 elevation, is difficult. Here we present three cases of IgG4-seronegative AIP and sclerosing cholangitis that responded to empiric steroid therapy and discuss approach considerations. These cases demonstrate the value of meticulous application of existing diagnostic algorithms to achieve a clinical diagnosis and avoid surgical intervention.

A Label-Free Immunosensor for IgG Based on an Extended-Gate Type Organic Field Effect Transistor

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Tsukuru Minamiki

2014-09-01

Full Text Available A novel biosensor for immunoglobulin G (IgG detection based on an extended-gate type organic field effect transistor (OFET has been developed that possesses an anti-IgG antibody on its extended-gate electrode and can be operated below 3 V. The titration results from the target IgG in the presence of a bovine serum albumin interferent, clearly exhibiting a negative shift in the OFET transfer curve with increasing IgG concentration. This is presumed to be due an interaction between target IgG and the immobilized anti-IgG antibody on the extended-gate electrode. As a result, a linear range from 0 to 10 µg/mL was achieved with a relatively low detection limit of 0.62 µg/mL (=4 nM. We believe that these results open up opportunities for applying extended-gate-type OFETs to immunosensing.

Clinical significance of anti-domain 1 β2-glycoprotein I antibodies in antiphospholipid syndrome.

Science.gov (United States)

Iwaniec, Teresa; Kaczor, Marcin P; Celińska-Löwenhoff, Magdalena; Polański, Stanisław; Musiał, Jacek

2017-05-01

Antiphospholipid syndrome (APS) is characterized by the presence of circulating antiphospholipid antibodies (aPL) in patients with thrombosis and/or pregnancy morbidity. In APS patients anti-domain 1 β2-glycoprotein I (anti-D1 β2GPI) IgG antibodies correlate strongly with thrombosis and to the lesser extent, with pregnancy complications. The aim of this study was to assess clinical utility of the anti-D1 β2GPI antibodies in the diagnosis and risk stratification of antiphospholipid syndrome. In this retrospective study 202 autoimmune patients were studied (primary APS - 58, secondary - 45 SLE - 99). Anticardiolipin (aCL) and anti-β 2 GPI (aβ 2 GPI antibodies) (IgG and IgM class) together with anti-D1 IgG were tested with QUANTA Flash chemiluminescent immunoassay and lupus anticoagulant (LA) with coagulometric methods. The highest anti-D1 values were observed in triple positive patients as compared to patients with other antiphospholipid antibody profiles. A strong correlation was found between levels of anti-D1 IgG and a β2GPI IgG antibodies for all patients analyzed (Spearman's ρ=0.87; p<0.0001). Anti-D1 IgG antibodies increase specificity resulting from classic aPL positivity but at the expense of sensitivity. Anti-D1 test does not add accuracy in predicting APS thrombotic complications on the top of accuracy offered by classic aPL tests and their profiles. Anti-D1 IgG antibodies did not add diagnostic power to the standard laboratory aPL tests as assessed by this retrospective study. A true clinical significance of anti-D1 antibodies in thrombotic risk stratification of aPL positive patients will require a properly designed clinical prospective trials. Copyright © 2017 Elsevier Ltd. All rights reserved.

HTR core physics analysis at NRG

International Nuclear Information System (INIS)

Kuijper, J.C.; Haas, J.B.M. de; Oppe, J.

2002-01-01

Since a number of years NRG is developing the HTR reactor physics code system PANTHERMIX. In PANTHERMIX the 3-D steady-state and transient core physics code PANTHER has been interfaced with the HTR thermal hydraulics code THERMIX to enable core follow and transient analyses on both pebble bed and block type HTR systems. Recently the capabilities of PANTHERMIX have been extended with the possibility to simulate the flow of pebbles through the core cavity and the (re)loading of pebbles on top of the core.The PANTHERMIX code system is being applied for the benchmark exercises for the Chinese HTR-10 and Japanese HTTR first criticality, calculating the critical loading, control rod worth and the isothermal temperature coefficients at zero power conditions. Also core physics calculations have been performed on an early version the South African PBMR design. The reactor physics properties of the reactor at equilibrium core loading have been studied as well as a selected run-in scenario, starting form fresh fuel. The recently developed reload option of PANTHERMIX was used extensively in these analyses. The examples shown demonstrate the capabilities of PANTHERMIX for performing steady-state and transient HTR core physics analyses. However, additional validation, especially for transient analyses, remains desirable. (author)

DNA-binding site of major regulatory protein alpha 4 specifically associated with promoter-regulatory domains of alpha genes of herpes simplex virus type 1.

OpenAIRE

Kristie, T M; Roizman, B

1986-01-01

Herpes simplex virus type 1 genes form at least five groups (alpha, beta 1, beta 2, gamma 1, and gamma 2) whose expression is coordinately regulated and sequentially ordered in a cascade fashion. Previous studies have shown that functional alpha 4 gene product is essential for the transition from alpha to beta protein synthesis and have suggested that alpha 4 gene expression is autoregulatory. We have previously reported that labeled DNA fragments containing promoter-regulatory domains of thr...

Viral RNA annealing activities of human immunodeficiency virus type 1 nucleocapsid protein require only peptide domains outside the zinc fingers.

Science.gov (United States)

De Rocquigny, H; Gabus, C; Vincent, A; Fournié-Zaluski, M C; Roques, B; Darlix, J L

1992-07-15

The nucleocapsid (NC) of human immunodeficiency virus type 1 consists of a large number of NC protein molecules, probably wrapping the dimeric RNA genome within the virion inner core. NC protein is a gag-encoded product that contains two zinc fingers flanked by basic residues. In human immunodeficiency virus type 1 virions, NCp15 is ultimately processed into NCp7 and p6 proteins. During virion assembly the retroviral NC protein is necessary for core formation and genomic RNA encapsidation, which are essential for virus infectivity. In vitro NCp15 activates viral RNA dimerization, a process most probably linked in vivo to genomic RNA packaging, and replication primer tRNA(Lys,3) annealing to the initiation site of reverse transcription. To characterize the domains of human immunodeficiency virus type 1 NC protein necessary for its various functions, the 72-amino acid NCp7 and several derived peptides were synthesized in a pure form. We show here that synthetic NCp7 with or without the two zinc fingers has the RNA annealing activities of NCp15. Further deletions of the N-terminal 12 and C-terminal 8 amino acids, leading to a 27-residue peptide lacking the finger domains, have little or no effect on NC protein activity in vitro. However deletion of short sequences containing basic residues flanking the first finger leads to a complete loss of NC protein activity. It is proposed that the basic residues and the zinc fingers cooperate to select and package the genomic RNA in vivo. Inhibition of the viral RNA binding and annealing activities associated with the basic residues flanking the first zinc finger of NC protein could therefore be used as a model for the design of antiviral agents.

Syntaxin binding protein 1 is not required for allergic inflammation via IgE-mediated mast cell activation.

Directory of Open Access Journals (Sweden)

Zhengli Wu

Full Text Available Mast cells play a central role in both innate and acquired immunity. When activated by IgE-dependent FcεRI cross-linking, mast cells rapidly initiate a signaling cascade and undergo an extensive release of their granule contents, including inflammatory mediators. Some SNARE (soluble N-ethylmaleimide-sensitive fusion factor attachment protein receptor proteins and SM (Sec1/Munc18 family proteins are involved in mast cell degranulation. However, the function of syntaxin binding protein 1 (STXBP1, a member of SM family, in mast cell degranulation is currently unknown. In this study, we examined the role of STXBP1 in IgE-dependent mast cell activation. Liver-derived mast cells (LMCs from wild-type and STXBP1-deficient mice were cultured in vitro for the study of mast cell maturation, degranulation, cytokine and chemokine production, as well as MAPK, IκB-NFκB, and NFAT signaling pathways. In addition, in vivo models of passive cutaneous anaphylaxis and late-phase IgE-dependent inflammation were conducted in mast cell deficient W(sh mice that had been reconstituted with wild-type or STXBP1-deficient mast cells. Our findings indicate that STXBP1 is not required for any of these important functional mechanisms in mast cells both in vitro and in vivo. Our results demonstrate that STXBP1 is dispensable during IgE-mediated mast cell activation and in IgE-dependent allergic inflammatory reactions.

A plasma cell differentiation quality control ablates B cell clones with biallelic Ig rearrangements and truncated Ig production.

Science.gov (United States)

Srour, Nivine; Chemin, Guillaume; Tinguely, Aurélien; Ashi, Mohamad Omar; Oruc, Zéliha; Péron, Sophie; Sirac, Christophe; Cogné, Michel; Delpy, Laurent

2016-01-11

Aberrantly rearranged immunoglobulin (Ig) alleles are frequent. They are usually considered sterile and innocuous as a result of nonsense-mediated mRNA decay. However, alternative splicing can yield internally deleted proteins from such nonproductively V(D)J-rearranged loci. We show that nonsense codons from variable (V) Igκ exons promote exon-skipping and synthesis of V domain-less κ light chains (ΔV-κLCs). Unexpectedly, such ΔV-κLCs inhibit plasma cell (PC) differentiation. Accordingly, in wild-type mice, rearrangements encoding ΔV-κLCs are rare in PCs, but frequent in B cells. Likewise, enforcing expression of ΔV-κLCs impaired PC differentiation and antibody responses without disturbing germinal center reactions. In addition, PCs expressing ΔV-κLCs synthesize low levels of Ig and are mostly found among short-lived plasmablasts. ΔV-κLCs have intrinsic toxic effects in PCs unrelated to Ig assembly, but mediated by ER stress-associated apoptosis, making PCs producing ΔV-κLCs highly sensitive to proteasome inhibitors. Altogether, these findings demonstrate a quality control checkpoint blunting terminal PC differentiation by eliminating those cells expressing nonfunctionally rearranged Igκ alleles. This truncated Ig exclusion (TIE) checkpoint ablates PC clones with ΔV-κLCs production and exacerbated ER stress response. The TIE checkpoint thus mediates selection of long-lived PCs with limited ER stress supporting high Ig secretion, but with a cost in terms of antigen-independent narrowing of the repertoire. © 2016 Srour et al.

The interaction of hepatitis A virus (HAV with soluble forms of its cellular receptor 1 (HAVCR1 share the physiological requirements of infectivity in cell culture

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Kaplan Gerardo G

2009-10-01

Full Text Available Abstract Background Hepatitis A virus (HAV, an atypical Picornaviridae that causes acute hepatitis in humans, usurps the HAV cellular receptor 1 (HAVCR1 to infect cells. HAVCR1 is a class 1 integral membrane glycoprotein that contains two extracellular domains: a virus-binding immunoglobulin-like (IgV domain and a mucin-like domain that extends the IgV from the cell membrane. Soluble forms of HAVCR1 bind, alter, and neutralize cell culture-adapted HAV, which is attenuated for humans. However, the requirements of the HAV-HAVCR1 interaction have not been fully characterized, and it has not been determined whether HAVCR1 also serves as a receptor for wild-type (wt HAV. Here, we used HAV soluble receptor neutralization and alteration assays to study the requirements of the HAV-HAVCR1 interaction and to determine whether HAVCR1 is also a receptor for wt HAV. Results Treatment of HAV with a soluble form of HAVCR1 that contained the IgV and two-thirds of the mucin domain fused to the Fc fragment of human IgG1 (D1 muc-Fc, altered particles at 37°C but left a residual level of unaltered particles at 4°C. The kinetics of neutralization of HAV by D1 muc-Fc was faster at 37°C than at 4°C. Alteration of HAV particles by D1 muc-Fc required Ca, which could not be replaced by Li, Na, Mg, Mn, or Zn. Neutralization of HAV by D1 muc-Fc occurred at pH 5 to 8 but was more efficient at pH 6 to 7. D1 muc-Fc neutralized wt HAV as determined by a cell culture system that allows the growth of wt HAV. Conclusion The interaction of HAV with soluble forms of HAVCR1 shares the temperature, Ca, and pH requirements for infectivity in cell culture and therefore mimics the cell entry process of HAV. Since soluble forms of HAVCR1 also neutralized wt HAV, this receptor may play a significant role in pathogenesis of HAV.

Containment Domains: A Scalable, Efficient and Flexible Resilience Scheme for Exascale Systems

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Jinsuk Chung

2013-01-01

Full Text Available This paper describes and evaluates a scalable and efficient resilience scheme based on the concept of containment domains. Containment domains are a programming construct that enable applications to express resilience needs and to interact with the system to tune and specialize error detection, state preservation and restoration, and recovery schemes. Containment domains have weak transactional semantics and are nested to take advantage of the machine and application hierarchies and to enable hierarchical state preservation, restoration and recovery. We evaluate the scalability and efficiency of containment domains using generalized trace-driven simulation and analytical analysis and show that containment domains are superior to both checkpoint restart and redundant execution approaches.

Investigation of alleged releases of the High Flux Reactor (HFR) in Petten, Netherlands. Measured data from the Nuclear Research and consultancy Group (NRG) in the period September 2001; Onderzoek naar vermeende lozingen HFR Petten. Meetgegevens van NRG in de periode september 2001

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-07-15

During the open house at the Nuclear Research and consultancy Group (NRG) on May 28th 2006 NRG publicly presented the measuring values of the Central Radiological Monitoring System (CRM). On detailed inquiry of a visitor strongly increased brief peak values appeared on 19 and 26 September 2001. This resulted in questions from many parties (Meldpunt Nucleaire Veiligheid Noord-Holland (Registration office Nuclear Safety North Holland), Provinciale States North Holland, Greenpeace Netherlands and Vereniging Pettemerduinen Kernreactorvrij (Association against Nuclear reactor in the dunes of Petten)) about a possible radiological emission. The press reported a radioactive gas cloud. The Department of Nuclear Safety, Security and Safeguards of the Netherlands Ministry of Housing, Spatial Planning and the Environment has examined the circumstances. The following research questions were examined: (1) How is the CRM system composed? (2) Has there been a radiological emission? (3) How can the peak values be explained? (4) What conclusions can be drawn from the National Measuring network for Radiology of the RIVM? [mk]. [Dutch] Tijdens een open dag bij Nuclear Research and consultancy Group (NRG) op 28 mei 2006 werden door NRG publiekelijk meetwaarden gepresenteerd van het Centraal Radiologisch Monitoring Systeem (CRM). Bij gedetailleerde navraag van een bezoeker manifesteerden zich op twee dagen, 19 en 26 september 2001, sterk verhoogde kort durende piekwaarden. Dit heeft ertoe geleid dat van diverse zijden (Meldpunt Nucleaire Veiligheid Noord-Holland, Provinciale Staten Noord-Holland, Greenpeace Nederland en Vereniging Pettemerduinen Kernreactorvrij!) de KFD vragen bereikten of er sprake zou kunnen zijn van een radiologische emissie. In de publiciteit werd gewag gemaakt van een 'radioactieve gaswolk'. De KFD van de VROM-Inspectie heeft de toedracht hiervan onderzocht. Hierbij zijn de volgende onderzoeksvragen gesteld: (1) Hoe zit het CRM-systeem in elkaar?; (2) Is

In-depth analysis of subclass-specific conformational preferences of IgG antibodies

DEFF Research Database (Denmark)

Tian, Xinsheng; Vestergaard, Bente; Thorolfsson, Matthias

2015-01-01

IgG subclass-specific differences in biological function and in vitro stability are often referred to variations in the conformational flexibility, while this flexibility has rarely been characterized. Here, small-angle X-ray scattering data from IgG1, IgG2 and IgG4 antibodies, which were designe...... properties and tailored effector functions. In addition, this advanced computational approach is applicable to other flexible multi-domain systems and extends the potential for investigating flexibility in solutions of macromolecules by small-angle X-ray scattering....

Conformational plasticity at the IgE-binding site of the B-cell receptor CD23.

Science.gov (United States)

Dhaliwal, Balvinder; Pang, Marie O Y; Yuan, Daopeng; Yahya, Norhakim; Fabiane, Stella M; McDonnell, James M; Gould, Hannah J; Beavil, Andrew J; Sutton, Brian J

2013-12-01

IgE antibodies play a central role in allergic disease. They recognize allergens via their Fab regions, whilst their effector functions are controlled through interactions of the Fc region with two principal cell surface receptors, FcɛRI and CD23. Crosslinking of FcɛRI-bound IgE on mast cells and basophils by allergen initiates an immediate inflammatory response, while the interaction of IgE with CD23 on B-cells regulates IgE production. We have determined the structures of the C-type lectin "head" domain of CD23 from seven crystal forms. The thirty-five independent structures reveal extensive conformational plasticity in two loops that are critical for IgE binding. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

75 FR 75994 - Application To Export Electric Energy; NRG Power Marketing LLC

Science.gov (United States)

2010-12-07

... Marketing LLC AGENCY: Office of Electricity Delivery and Energy Reliability, DOE. ACTION: Notice of application. SUMMARY: NRG Power Marketing LLC (NRGPML) has applied to renew its authority to transmit electric... to Canada would be surplus energy purchased from electric utilities, Federal power marketing agencies...

Ultraviolet Detection of the Binary Companion to the Type IIb SN 2001ig

Science.gov (United States)

Ryder, Stuart D.; Van Dyk, Schuyler D.; Fox, Ori D.; Zapartas, Emmanouil; de Mink, Selma E.; Smith, Nathan; Brunsden, Emily; Azalee Bostroem, K.; Filippenko, Alexei V.; Shivvers, Isaac; Zheng, WeiKang

2018-03-01

We present HST/WFC3 ultraviolet imaging in the F275W and F336W bands of the Type IIb SN 2001ig at an age of more than 14 years. A clear point source is detected at the site of the explosion, with m F275W = 25.39 ± 0.10 and m F336W = 25.88 ± 0.13 mag. Despite weak constraints on both the distance to the host galaxy NGC 7424 and the line-of-sight reddening to the supernova, this source matches the characteristics of an early B-type main-sequence star with 19,000 GMOS optical spectrum at an age of 6 years reveals a narrow He II λ4686 emission line, indicative of continuing interaction with a dense circumstellar medium at large radii from the progenitor. We review our findings on SN 2001ig in the context of binary evolution channels for stripped-envelope supernovae. Owing to the uncrowded nature of its environment in the ultraviolet, this study of SN 2001ig represents one of the cleanest detections to date of a surviving binary companion to a Type IIb supernova.

Analysis of O-glycan heterogeneity in IgA1 myeloma proteins by Fourier transform ion cyclotron resonance mass spectrometry: implications for IgA nephropathy

DEFF Research Database (Denmark)

Renfrow, MB; Mackay, CL; Chalmers, MJ

2007-01-01

deficiency in IgA1 proteins occurs randomly or preferentially at specific sites. We have previously demonstrated the first direct localization of multiple O-glycosylation sites on a single IgA1 myeloma protein by use of activated ion-electron capture dissociation (AI-ECD) Fourier transform ion cyclotron...... resonance (FT-ICR) tandem mass spectrometry. Here, we report the analysis of IgA1 O-glycan heterogeneity by use of FT-ICR MS and liquid chromatography FT-ICR MS to obtain unbiased accurate mass profiles of IgA1 HR glycopeptides from three different IgA1 myeloma proteins. Additionally, we report the first AI......-ECD fragmentation on an individual IgA1 O-glycopeptide from an IgA1 HR preparation that is reproducible for each IgA1 myeloma protein. These results suggest that future analysis of IgA1 HR from IgAN patients and normal healthy controls should be feasible....

The C-type lectin of the aggrecan G3 domain activates complement.

Directory of Open Access Journals (Sweden)

Camilla Melin Fürst

Full Text Available Excessive complement activation contributes to joint diseases such as rheumatoid arthritis and osteoarthritis during which cartilage proteins are fragmented and released into the synovial fluid. Some of these proteins and fragments activate complement, which may sustain inflammation. The G3 domain of large cartilage proteoglycan aggrecan interacts with other extracellular matrix proteins, fibulins and tenascins, via its C-type lectin domain (CLD and has important functions in matrix organization. Fragments containing G3 domain are released during normal aggrecan turnover, but increasingly so in disease. We now show that the aggrecan CLD part of the G3 domain activates the classical and to a lesser extent the alternative pathway of complement, via binding of C1q and C3, respectively. The complement control protein (CCP domain adjacent to the CLD showed no effect on complement initiation. The binding of C1q to G3 depended on ionic interactions and was decreased in D2267N mutant G3. However, the observed complement activation was attenuated due to binding of complement inhibitor factor H to CLD and CCP domains. This was most apparent at the level of deposition of terminal complement components. Taken together our observations indicate aggrecan CLD as one factor involved in the sustained inflammation of the joint.

An ice-binding and tandem beta-sandwich domain-containing protein in Shewanella frigidimarina is a potential new type of ice adhesin.

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Vance, Tyler D R; Graham, Laurie A; Davies, Peter L

2018-04-01

Out of the dozen different ice-binding protein (IBP) structures known, the DUF3494 domain is the most widespread, having been passed many times between prokaryotic and eukaryotic microorganisms by horizontal gene transfer. This ~25-kDa β-solenoid domain with an adjacent parallel α-helix is most commonly associated with an N-terminal secretory signal peptide. However, examples of the DUF3494 domain preceded by tandem Bacterial Immunoglobulin-like (BIg) domains are sometimes found, though uncharacterized. Here, we present one such protein (SfIBP_1) from the Antarctic bacterium Shewanella frigidimarina. We have confirmed and characterized the ice-binding activity of its ice-binding domain using thermal hysteresis measurements, fluorescent ice plane affinity analysis, and ice recrystallization inhibition assays. X-ray crystallography was used to solve the structure of the SfIBP_1 ice-binding domain, to further characterize its ice-binding surface and unique method of stabilizing or 'capping' the ends of the solenoid structure. The latter is formed from the interaction of two loops mediated by a combination of tandem prolines and electrostatic interactions. Furthermore, given their domain architecture and membrane association, we propose that these BIg-containing DUF3494 IBPs serve as ice-binding adhesion proteins that are capable of adsorbing their host bacterium onto ice. Submitted new structure to the Protein Data Bank (PDB: 6BG8). © 2018 Federation of European Biochemical Societies.

Infection of CD4+ T lymphocytes by the human T cell leukemia virus type 1 is mediated by the glucose transporter GLUT-1: Evidence using antibodies specific to the receptor's large extracellular domain

International Nuclear Information System (INIS)

Jin, Qingwen; Agrawal, Lokesh; VanHorn-Ali, Zainab; Alkhatib, Ghalib

2006-01-01

To analyze HTLV-1 cytotropism, we developed a highly sensitive vaccinia virus-based assay measuring activation of a reporter gene upon fusion of two distinct cell populations. We used this system in a functional cDNA screening to isolate and confirm that the glucose transporter protein 1 (GLUT-1) is a receptor for HTLV-1. GLUT-1 is a ubiquitously expressed plasma membrane glycoprotein with 12 transmembrane domains and 6 extracellular loops (ECL). We demonstrate for the first time that peptide antibodies (GLUT-IgY) raised in chicken to the large extracellular loop (ECL1) detect GLUT-1 at the cell surface and inhibit envelope (Env)-mediated fusion and infection. Efficient GLUT-IgY staining was detected with peripheral blood CD4 + lymphocytes purified by positive selection. Further, GLUT-IgY caused efficient inhibition of Env-mediated fusion and infection of CD4 + T and significantly lower inhibition of CD8 + T lymphocytes. The specificity of GLUT-IgY antibodies to GLUT-1 was demonstrated by ECL1 peptide competition studies. Grafting ECL1 of GLUT-1 onto the receptor-negative GLUT-3 conferred significant receptor activity. In contrast, grafting ECL1 of GLUT-3 onto GLUT-1 resulted in a significant loss of the receptor activity. The ECL1-mediated receptor activity was efficiently blocked with four different human monoclonal antibody (HMab) to HTLV-1 Env. The ECL1-derived peptide blocked HTLV-1 Env-mediated fusion with several nonhuman mammalian cell lines. The results demonstrate the utilization of cell surface GLUT-1 in HTLV-1 infection of CD4 + T lymphocytes and implicate a critical role for the ECL1 region in viral tropism

IgE antibodies, FcεRIα, and IgE-mediated local anaphylaxis can limit snake venom toxicity.

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Starkl, Philipp; Marichal, Thomas; Gaudenzio, Nicolas; Reber, Laurent Lionel; Sibilano, Riccardo; Tsai, Mindy; Galli, Stephen Joseph

2016-01-01

Type 2 cytokine-related immune responses associated with development of antigen-specific IgE antibodies can contribute to pathology in patients with allergic diseases and to fatal anaphylaxis. However, recent findings in mice indicate that IgE also can enhance defense against honeybee venom. We tested whether IgE antibodies, IgE-dependent effector mechanisms, and a local anaphylactic reaction to an unrelated antigen can enhance defense against Russell viper venom (RVV) and determined whether such responses can be influenced by immunization protocol or mouse strain. We compared the resistance of RVV-immunized wild-type, IgE-deficient, and Fcer1a-deficient mice after injection of a potentially lethal dose of RVV. A single prior exposure to RVV enhanced the ability of wild-type mice, but not mice lacking IgE or functional FcεRI, to survive challenge with a potentially lethal amount of RVV. Moreover, IgE-dependent local passive cutaneous anaphylaxis in response to challenge with an antigen not naturally present in RVV significantly enhanced resistance to the venom. Finally, we observed different effects on resistance to RVV or honeybee venom in BALB/c versus C57BL/6 mice that had received a second exposure to that venom before challenge with a high dose of that venom. These observations illustrate the potential benefit of IgE-dependent effector mechanisms in acquired host defense against venoms. The extent to which type 2 immune responses against venoms can decrease pathology associated with envenomation seems to be influenced by the type of venom, the frequency of venom exposure, and the genetic background of the host. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Perivascular Adipose Tissue Harbors Atheroprotective IgM-Producing B Cells

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Prasad Srikakulapu

2017-09-01

Full Text Available Adipose tissue surrounding major arteries (Perivascular adipose tissue or PVAT has long been thought to exist to provide vessel support and insulation. Emerging evidence suggests that PVAT regulates artery physiology and pathology, such as, promoting atherosclerosis development through local production of inflammatory cytokines. Yet the immune subtypes in PVAT that regulate inflammation are poorly characterized. B cells have emerged as important immune cells in the regulation of visceral adipose tissue inflammation and atherosclerosis. B cell-mediated effects on atherosclerosis are subset-dependent with B-1 cells attenuating and B-2 cells aggravating atherosclerosis. While mechanisms whereby B-2 cells aggravate atherosclerosis are less clear, production of immunoglobulin type M (IgM antibodies is thought to be a major mechanism whereby B-1 cells limit atherosclerosis development. B-1 cell-derived IgM to oxidation specific epitopes (OSE on low density lipoproteins (LDL blocks oxidized LDL-induced inflammatory cytokine production and foam cell formation. However, whether PVAT contains B-1 cells and whether atheroprotective IgM is produced in PVAT is unknown. Results of the present study provide clear evidence that the majority of B cells in and around the aorta are derived from PVAT. Interestingly, a large proportion of these B cells belong to the B-1 subset with the B-1/B-2 ratio being 10-fold higher in PVAT relative to spleen and bone marrow. Moreover, PVAT contains significantly greater numbers of IgM secreting cells than the aorta. ApoE−/− mice with B cell-specific knockout of the gene encoding the helix-loop-helix factor Id3, known to have attenuated diet-induced atherosclerosis, have increased numbers of B-1b cells and increased IgM secreting cells in PVAT relative to littermate controls. Immunostaining of PVAT on human coronary arteries identified fat associated lymphoid clusters (FALCs harboring high numbers of B cells, and flow

IgE versus IgG4 epitopes of the peanut allergen Ara h 1 in patients with severe allergy

DEFF Research Database (Denmark)

Bøgh, Katrine Lindholm; Nielsen, H.; Eiwegger, T.

2014-01-01

epitopes. Objective: The aim of this study was to compare Ara h 1-specific IgE and IgG4 epitope recognition patterns in patients with severe peanut allergy, applying a method allowing for identification of both linear and conformational epitopes. Methods: Polyclonal sera from three individual patients......, suffering from severe allergic reaction to peanuts, including anaphylaxis, were used to analyse the IgE and IgG4 epitope recognition patterns of the major peanut allergen Ara h 1. Epitope identification was conducted by competitive immuno-screening of a phage-displayed random heptamer peptide library...

Microbial F-type lectin domains with affinity for blood group antigens.

Science.gov (United States)

Mahajan, Sonal; Khairnar, Aasawari; Bishnoi, Ritika; Ramya, T N C

2017-09-23

F-type lectins are fucose binding lectins with characteristic fucose binding and calcium binding motifs. Although they occur with a selective distribution in viruses, prokaryotes and eukaryotes, most biochemical studies have focused on vertebrate F-type lectins. Recently, using sensitive bioinformatics search techniques on the non-redundant database, we had identified many microbial F-type lectin domains with diverse domain organizations. We report here the biochemical characterization of F-type lectin domains from Cyanobium sp. PCC 7001, Myxococcus hansupus and Leucothrix mucor. We demonstrate that while all these three microbial F-type lectin domains bind to the blood group H antigen epitope on fucosylated glycans, there are fine differences in their glycan binding specificity. Cyanobium sp. PCC 7001 F-type lectin domain binds exclusively to extended H type-2 motif, Myxococcus hansupus F-type lectin domain binds to B, H type-1 and Lewis b motifs, and Leucothrix mucor F-type lectin domain binds to a wide range of fucosylated glycans, including A, B, H and Lewis antigens. We believe that these microbial lectins will be useful additions to the glycobiologist's toolbox for labeling, isolating and visualizing glycans. Copyright © 2017 Elsevier Inc. All rights reserved.

HIGH-VELOCITY LINE FORMING REGIONS IN THE TYPE Ia SUPERNOVA 2009ig

International Nuclear Information System (INIS)

Marion, G. H.; Foley, Ryan J.; Challis, Peter; Kirshner, Robert P.; Vinko, Jozsef; Wheeler, J. Craig; Silverman, Jeffrey M.; Hsiao, Eric Y.; Brown, Peter J.; Filippenko, Alexei V.; Garnavich, Peter; Landsman, Wayne B.; Parrent, Jerod T.; Pritchard, Tyler A.; Roming, Peter W. A.; Wang, Xiaofeng

2013-01-01

We report measurements and analysis of high-velocity (HVF) (>20,000 km s –1 ) and photospheric absorption features in a series of spectra of the Type Ia supernova (SN) 2009ig obtained between –14 days and +13 days with respect to the time of maximum B-band luminosity (B-max). We identify lines of Si II, Si III, S II, Ca II, and Fe II that produce both HVF and photospheric-velocity (PVF) absorption features. SN 2009ig is unusual for the large number of lines with detectable HVF in the spectra, but the light-curve parameters correspond to a slightly overluminous but unexceptional SN Ia (M B = –19.46 mag and Δm 15 (B) = 0.90 mag). Similarly, the Si II λ6355 velocity at the time of B-max is greater than 'normal' for an SN Ia, but it is not extreme (v Si = 13,400 km s –1 ). The –14 days and –13 days spectra clearly resolve HVF from Si II λ6355 as separate absorptions from a detached line forming region. At these very early phases, detached HVF are prevalent in all lines. From –12 days to –6 days, HVF and PVF are detected simultaneously, and the two line forming regions maintain a constant separation of about 8000 km s –1 . After –6 days all absorption features are PVF. The observations of SN 2009ig provide a complete picture of the transition from HVF to PVF. Most SNe Ia show evidence for HVF from multiple lines in spectra obtained before –10 days, and we compare the spectra of SN 2009ig to observations of other SNe. We show that each of the unusual line profiles for Si II λ6355 found in early-time spectra of SNe Ia correlate to a specific phase in a common development sequence from HVF to PVF

IgE epitopes of intact and digested Ara h 1

DEFF Research Database (Denmark)

Bøgh, Katrine Lindholm; Nielsen, H.; Madsen, Charlotte Bernhard

2012-01-01

epitopes have been suggested to be of great importance. ObjectiveThe aim of this study was to identify IgE specific epitopes of intact and digested Ara h 1, and to compare epitope patterns between humans and rats. MethodsSera from five peanut allergic patients and five Brown Norway rats were used...... to identify intact and digested Ara h 1-specific IgE epitopes by competitive immunoscreening of a phage-displayed random hepta-mer peptide library using polyclonal IgE from the individual sera. The resulting peptide sequences were mapped on the surface of a three-dimensional structure of the Ara h 1 molecule...... to mimic epitopes using a computer-based algorithm. ResultsPatients as well as rats were shown to have individual IgE epitope patterns. All epitope mimics were conformational and found to cluster into three different areas of the Ara h 1 molecule. Five epitope motifs were identified by patient IgE, which...

Phenotypic effects of maternal immune activation and early postnatal milieu in mice mutant for the schizophrenia risk gene neuregulin-1.

Science.gov (United States)

O'Leary, C; Desbonnet, L; Clarke, N; Petit, E; Tighe, O; Lai, D; Harvey, R; Waddington, J L; O'Tuathaigh, C

2014-09-26

Risk of schizophrenia is likely to involve gene × environment (G × E) interactions. Neuregulin 1 (NRG1) is a schizophrenia risk gene, hence any interaction with environmental adversity, such as maternal infection, may provide further insights into the basis of the disease. This study examined the individual and combined effects of prenatal immune activation with polyriboinosinic-polyribocytidilic acid (Poly I:C) and disruption of the schizophrenia risk gene NRG1 on the expression of behavioral phenotypes related to schizophrenia. NRG1 heterozygous (NRG1 HET) mutant breeding pairs were time-mated. Pregnant dams received a single injection (5mg/kg i.p.) of Poly I:C or vehicle on gestation day 9 (GD9). Offspring were then cross-fostered to vehicle-treated or Poly I:C-treated dams. Expression of schizophrenia-related behavioral endophenotypes was assessed at adolescence and in adulthood. Combining NRG1 disruption and prenatal environmental insult (Poly I:C) caused developmental stage-specific deficits in social behavior, spatial working memory and prepulse inhibition (PPI). However, combining Poly I:C and cross-fostering produced a number of behavioral deficits in the open field, social behavior and PPI. This became more complex by combining NRG1 deletion with both Poly I:C exposure and cross-fostering, which had a robust effect on PPI. These findings suggest that concepts of G × E interaction in risk of schizophrenia should be elaborated to multiple interactions that involve individual genes interacting with diverse biological and psychosocial environmental factors over early life, to differentially influence particular domains of psychopathology, sometimes over specific stages of development. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Dynamics of Inter-heavy Chain Interactions in Human Immunoglobulin G (IgG) Subclasses Studied by Kinetic Fab Arm Exchange

NARCIS (Netherlands)

Rispens, Theo; Davies, Anna M.; Ooijevaar-de Heer, Pleuni; Absalah, Samira; Bende, Onno; Sutton, Brian J.; Vidarsson, Gestur; Aalberse, Rob C.

2014-01-01

Background: Fab arm exchange requires weak interactions between CH3 domains, such as in human IgG4. Results: CH3-CH3 interactions differ >1,000,000-fold between human subclasses and allotypes due to variations Lys/Asn-392, Val/Met-397, and Lys/Arg-409. Conclusion: For IgG2 and IgG3, but not IgG1,

Human IgG4 binds to IgG4 and conformationally altered IgG1 via Fc-Fc interactions

NARCIS (Netherlands)

Rispens, Theo; Ooievaar-de Heer, Pleuni; Vermeulen, Ellen; Schuurman, Janine; van der Neut Kolfschoten, Marijn; Aalberse, Rob C.

2009-01-01

The Fc fragment of IgG4 can interact with the Fc fragment of another IgG molecule. This interaction is a confounding factor when measuring IgG4 rheumatoid factor levels. Recently, we demonstrated that half-molecules of IgG4 can exchange to form a bispecific Ab. We expected these two phenomena to be

[IgE myeloma. Laboratory typing difficulties].

Science.gov (United States)

Bovone, Nora S; Fuente, María Cristina; Gastiazoro, Ana María; Alfonso, Graciela; Freitas, María Josefina

2014-01-01

The IgE multiple myeloma is a rare neoplasm of plasma cell accounting for 0.01% of all plasma cell dyscrasias. They are generally of more aggressive development and to date there are no more than 50 cases published in current literature. Laboratory studies are, in these cases, essential for the classification of the monoclonal component in serum and urine. The aim of this presentation is to report a patient diagnosed with IgE myeloma and to point out that the laboratory difficulties noted in these rare cases can lead to an erroneous report.

Solution structure of leptospiral LigA4 Big domain

Energy Technology Data Exchange (ETDEWEB)

Mei, Song; Zhang, Jiahai [Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China); Zhang, Xuecheng [School of Life Sciences, Anhui University, Hefei, Anhui 230039 (China); Tu, Xiaoming, E-mail: xmtu@ustc.edu.cn [Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China)

2015-11-13

Pathogenic Leptospiraspecies express immunoglobulin-like proteins which serve as adhesins to bind to the extracellular matrices of host cells. Leptospiral immunoglobulin-like protein A (LigA), a surface exposed protein containing tandem repeats of bacterial immunoglobulin-like (Big) domains, has been proved to be involved in the interaction of pathogenic Leptospira with mammalian host. In this study, the solution structure of the fourth Big domain of LigA (LigA4 Big domain) from Leptospira interrogans was solved by nuclear magnetic resonance (NMR). The structure of LigA4 Big domain displays a similar bacterial immunoglobulin-like fold compared with other Big domains, implying some common structural aspects of Big domain family. On the other hand, it displays some structural characteristics significantly different from classic Ig-like domain. Furthermore, Stains-all assay and NMR chemical shift perturbation revealed the Ca{sup 2+} binding property of LigA4 Big domain. - Highlights: • Determining the solution structure of a bacterial immunoglobulin-like domain from a surface protein of Leptospira. • The solution structure shows some structural characteristics significantly different from the classic Ig-like domains. • A potential Ca{sup 2+}-binding site was identified by strains-all and NMR chemical shift perturbation.

Solution structure of leptospiral LigA4 Big domain

International Nuclear Information System (INIS)

Mei, Song; Zhang, Jiahai; Zhang, Xuecheng; Tu, Xiaoming

2015-01-01

Pathogenic Leptospiraspecies express immunoglobulin-like proteins which serve as adhesins to bind to the extracellular matrices of host cells. Leptospiral immunoglobulin-like protein A (LigA), a surface exposed protein containing tandem repeats of bacterial immunoglobulin-like (Big) domains, has been proved to be involved in the interaction of pathogenic Leptospira with mammalian host. In this study, the solution structure of the fourth Big domain of LigA (LigA4 Big domain) from Leptospira interrogans was solved by nuclear magnetic resonance (NMR). The structure of LigA4 Big domain displays a similar bacterial immunoglobulin-like fold compared with other Big domains, implying some common structural aspects of Big domain family. On the other hand, it displays some structural characteristics significantly different from classic Ig-like domain. Furthermore, Stains-all assay and NMR chemical shift perturbation revealed the Ca"2"+ binding property of LigA4 Big domain. - Highlights: • Determining the solution structure of a bacterial immunoglobulin-like domain from a surface protein of Leptospira. • The solution structure shows some structural characteristics significantly different from the classic Ig-like domains. • A potential Ca"2"+-binding site was identified by strains-all and NMR chemical shift perturbation.

77 FR 11515 - Application to Export Electric Energy; NRG Power Marketing LLC

Science.gov (United States)

2012-02-27

... DEPARTMENT OF ENERGY [OE Docket No. EA-384] Application to Export Electric Energy; NRG Power... electric energy from the United States to Mexico pursuant to section 202(e) of the Federal Power Act (FPA... requested. The electric energy that NRGPML proposes to export to Mexico would be surplus energy purchased...

Cocoa and cocoa fibre differentially modulate IgA and IgM production at mucosal sites.

Science.gov (United States)

Massot-Cladera, Malen; Franch, Àngels; Pérez-Cano, Francisco J; Castell, Margarida

2016-05-01

Previous studies have shown that a 10 % cocoa (C10) diet, containing polyphenols and fibre among others, modifies intestinal and systemic Ig production. The present study aimed at evaluating the impact of C10 on IgA and IgM production in the intestinal and extra-intestinal mucosal compartments, establishing the involvement of cocoa fibre (CF) in such effects. Mechanisms by which C10 intake may affect IgA synthesis in the salivary glands were also studied. To this effect, rats were fed either a standard diet, a diet containing C10, CF or inulin. Intestinal (the gut wash (GW), Peyer's patches (PP) and mesenteric lymph nodes (MLN)) and extra-intestinal (salivary glands) mucosal tissues and blood samples were collected for IgA and IgM quantification. The gene expressions of IgA production- and homing-related molecules were studied in the salivary glands. The C10 diet decreased intestinal IgA and IgM production. Although the CF diet decreased the GW IgA concentration, it increased PP, MLN and serum IgA concentrations. Both the C10 and the CF diets produced a down-regulatory effect on IgA secretion in the extra-intestinal tissues. The C10 diet interacted with the mechanisms involved in IgA synthesis, whereas the CF showed particular effects on the homing and transcytosis of IgA across the salivary glands. Overall, CF was able to up-regulate IgA production in the intestinal-inductor compartments, whereas it down-regulated its production at the mucosal-effector ones. Further studies must be directed to ascertain the mechanisms involved in the effect of particular cocoa components on gut-associated lymphoid tissue.

Design and testing of a shock absorber for a type 1 container

International Nuclear Information System (INIS)

Sappok, M.; Beine, B.; Rittscher, D.

1993-01-01

A shock-absorber will be required for a rad. waste 'Konrad' type 1 container made of ductile cast iron whenever it will be used as a type B container according to the IAEA-Regulations for the Safe Transport of Radioactive materials. The shock-absorber has to protect the type B container during shipping such as to withstand the accident scenarios that are covered by the IAEA-Regulation tests without substantial loss of its shielding and tightness functions. The designation as type 1 container originates from German regulations for the intermediate storage site Gorleben and the final depository Konrad-mine. These regulations call for the limits on outside dimensions of 1700 mm in length, 1600 mm in width and 1450 mm in height as well as for a limit of 20 Mg on total weight without shock-absorber. The relatively simple design method for the shock-absorber has been validated by the test results. It can be extended to other materials and designs for shock-absorbers if reliable force-displacement-diagrams are available for the structural elements from which the absorbed energy and the displacements can be calculated by integration. In order to account for the dynamic effects, the better approximation of the true duration of the impact would be helpful. The present limit of 0.5 R p0,2 on the nominal stresses should be discussed because the large number of tests on containers made of ductile cast iron that have been performed up to now have shown a substantial level of conservatism on this respect. The sharply tapered pipes on edge Kl of the shock-absorbers should be replaced by pipe bends. This will result in smaller accelerations and in an even higher level of protection of the container than effected by the tested shock-absorber

Prevaccination Rotavirus Serum IgG and IgA Are Associated With Lower Immunogenicity of Live, Oral Human Rotavirus Vaccine in South African Infants.

Science.gov (United States)

Moon, Sung-Sil; Groome, Michelle J; Velasquez, Daniel E; Parashar, Umesh D; Jones, Stephanie; Koen, Antoinette; van Niekerk, Nadia; Jiang, Baoming; Madhi, Shabir A

2016-01-15

Live oral rotavirus (RV) vaccines have shown modest efficacy among children in African countries for reasons that are not completely understood. We examined the possible inhibitory effect of preexisting antirotavirus antibodies on immunogenicity of monovalent RV vaccine (RV1). Mother-infant pairs were enrolled at presentation for their routine immunization visit in Soweto, South Africa, when infants were aged 5-8 weeks. Infant serum samples were obtained before the first and second doses of RV1 and 1 month after the second dose. Maternal serum and breast milk samples were obtained prior to administration of each dose of RV1 to infants. RV-specific immunoglobulin G (IgG), IgA, and neutralizing activity in sera of infants and serum or breast milk samples of mothers were measured using enzyme-linked immunosorbent assays or a microneutralization test. Of the 107 serum pairs from infants who were seronegative for RV IgA at enrollment, we observed a strong positive association between IgG titers in pre-dose 1 sera of infants and mothers and significant negative associations between IgG titers in pre-dose 1 sera of infants and seroconversion to RV1 post-dose 1. Similarly, mothers whose infants' IgA seroconverted after RV1 had significantly lower pre-dose 1 IgG titers in sera than those whose infants did not seroconvert. High levels of preexisting serum IgG, including transplacentally acquired maternal IgG, appeared to have an inhibitory effect on the immunogenicity of RV1 among infants and may, in part, contribute to lower efficacy of RV vaccines in this and other low-income settings. Published by Oxford University Press for the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Serum IgG2 and tissue IgG2 plasma cell elevation in orbital IgG4-related disease (IgG4-RD): Potential use in IgG4-RD assessment.

Science.gov (United States)

Chan, Anita S Y; Mudhar, Hardeep; Shen, Sunny Yu; Lang, Stephanie S; Fernando, Malee; Hilmy, Maryam Hazly; Guppy, Naomi Jayne; Rennie, Ian; Dunkley, Lisa; Al Jajeh, Issam

2017-11-01

To determine the role of serum and tissue IgG2 in orbital biopsies with the histological features of IgG4-related disease (IgG4-RD) in comparison with non-IgG4-related orbital inflammatory disorders (OID), including autoimmune disorders. This is an international (Sheffield, UK, and Singapore) collaborative, retrospective case review of 69 patients (38 from Singapore National Eye Centre and 31 from Royal Hallamshire Hospital, Sheffield) with orbital inflammatory biopsies between 2002 and 2016. Clinical information and histology were reviewed and cases were classified into three groups: Group 1: IgG4-RD orbital inflammation (n=43); Group 2: idiopathic OID (n=12) and Group 3: autoimmune OID (n=14). Serum IgG1, IgG2, IgG3 and IgG4 levels were collated where available and immunohistochemistry (IHC) for tissue IgG2 plasma cells was performed. Dual IHC showed IgG2 plasma cells as a distinct population from IgG4 plasma cells. Significant (twofold) serum IgG2 elevation was noted among IgG4-RD (group 1), idiopathic (group 2) and autoimmune OID (group 3). Similarly, significant elevation of tissue IgG2 plasma cells was also seen among IgG4-RD (group 1), idiopathic and autoimmune OID (groups 2 and 3). Significant elevations of serum IgG2 and tissue IgG2 plasma cells are present in orbital IgG4-RD in comparison with non-IgG4 orbital inflammation (idiopathic and autoimmune OID), suggesting that IgG2 may play a role in IgG4-RD. A serum IgG2 cut-off >5.3 g/L was found to be 80% sensitive and 91.7% specific for orbital IgG4-RD, with an accuracy of 0.90. Tissue IgG2 and IgG4 subclass reporting may provide additional insight regarding the 'IgG4-RD' pathogenesis. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.